World War II by country



Nearly every country in the world participated in World War II, with the exception of a few states that remained neutral. The Second World War pitted two alliances against each other, the Axis powers and the Allied powers. The leading powers of the former were Nazi Germany, the Kingdom of Italy, and the Empire of Japan, while the United Kingdom and France with their colonial empires, China, the Soviet Union and the United States were the "Big Five" of the other camp.

The causes of the conflict originated among other things in the rise of fascism in Italy and Japan and of Nazism in a revanchist Germany after the treaty of Versailles that concluded its defeat in the First World War. Tensions created by their expansionism in Abyssinia, Manchuria, the Sudetenland and further beyond escalated until they exploded with the invasion of Poland in 1939.

While the Axis had the support of a handfuls of minor allies and client states, by 1945 almost every single country in the world had declared war on them, although many of them did so only at the eleventh hour.

National impacts
The countries involved in or affected by World War II are listed here alphabetically, with a brief description of their role in the conflict. Most of these countries listed had no direct effect on any country but were briefly attacked or affected in small ways.

Afghanistan
Afghanistan maintained its neutrality.

Albania
After the Italian invasion of Albania in April 1939, 100,000 Italian soldiers and 11,000 Italian colonists who wanted to integrate Albania into the Italian Empire settled in the country. Initially the Albanian Fascist Party received support from the population, mainly because of the unification of Kosovo and other Albanian-populated territories with Albania proper after the conquest of Yugoslavia and Greece by the Axis in Spring 1941. Benito Mussolini boasted in May 1941 to a group of Albanian fascists that he had achieved the Greater Albania long wanted by the Tirana nationalists. In October 1941, the small Albanian Communist groups established an Albanian Communist Party in Tirana of 130 members under the leadership of Enver Hoxha and an eleven-man Central Committee.

In mid-1942, however, party leaders increased their popularity by calling the young peoples to fight for the liberation of their country from Italy. This propaganda increased the number of new recruits by many young peoples eager for freedom. In September 1942, the party organized a popular front organization, the Albanian National Anti-Fascist Front, from a number of resistance groups, including several that were strongly anticommunist. During the war, the NLM's communist-dominated partisans, in the form of the National Liberation Army, did not heed warnings from the Italian occupiers that there would be reprisals for guerrilla attacks.

Germany occupied Albania in September 1943, dropping paratroopers into Tirana before the Albanian guerrillas could take the capital, and the German army soon drove the guerrillas into the hills and to the south. Berlin subsequently announced it would recognize the independence of a neutral Albania and organized an Albanian government, police, and military. Many Balli Kombëtar units cooperated with the Germans against the communists, and several Balli Kombëtar leaders held positions in the German-sponsored regime. The partisans entirely liberated Albania from German occupation on November 29, 1944. The Albanian partisans also helped in the liberation of Kosovo, part of Montenegro and southern Bosnia and Herzegovina. The National Liberation Army consisting of up to 70 thousand partisans, also took part in the war alongside the antifascist coalition. By that time, the Soviet Army was also entering neighboring Yugoslavia, and the German Army was evacuating from Greece into Yugoslavia.

American Samoa
American Samoa is an American territory and a U.S. Navy base, and was used during the war.

Argentina
During the period of World War II, Argentina was ruled by a series of nationalist governments and dictatorial military juntas. Neutralist feelings prevailed in the military, which saw the war as a potential source of economic benefit for the country, by exporting supplies and agricultural products to both sides of the conflict. The government of Edelmiro Julián Farrell eventually caved in to international pressure, and Argentina joined other Latin American countries and declared war on Germany and Japan, one month before the war was over (27 March 1945).

More than 750 Argentine volunteers fought in the British, South African and Canadian Air Forces, mainly in the 164 Argentine-British RAF squadron, which saw action in Northern France and Belgium. Nearly 4,000 Argentine volunteers fought on the Allied side.

Armenia
Armenia was spared the devastation and destruction that wrought most of the western Soviet Union during the Great Patriotic War of World War II. The Nazis never reached the South Caucasus. Armenia had a population of 1,320,000 at the beginning of the war in 1939 and an estimated 300–500,000 Armenians served in the war, almost half of whom did not return. More than 1,000 women from Armenia were recruited to the Soviet Armed Forces. A total of 117 citizens of Armenia including 10 non ethnic Armenians were awarded Hero of the Soviet Union. Of these, 36 had been killed in action and were awarded this title posthumously. 27 Armenian soldiers and sergeants were also awarded the Order of Glory, and a total of 66,802 participants from Armenia were awarded orders and medals of the Soviet Union. Armenians living in the areas occupied regions of the Soviet Union formed partisan groups to combat the Germans. Over sixty Armenians were promoted to the rank of general, and with an additional four eventually achieving the rank of Marshal of the Soviet Union. Hovhannes Bagramyan was both the first non-Slavic Marshal and commander to hold the position of front commander when he was assigned to be the commander of the First Baltic Front in 1943. Admiral Ivan Isakov became the second Admiral of the fleet of the Soviet Union. Hamazasp Babadzhanian was the second of only two Chief Marshal of the Tank and Armored Troops. Sergei Khudyakov had been among the third to be Marshal of Aviation. Six special military divisions were formed in Soviet Armenia in 1941-42, partly because so many draftees from the republic could not understand Russian. These six divisions alone had more than 67,000 soldiers. Five of them, the 89th, 409th, 408th, 390th, and 76th Divisions, would have a distinguished war record, while the sixth was ordered to stay in Armenia to guard the republic’s western borders against a possible incursion by neighboring Turkey. The 89th Tamanyan Division, composed of ethnic Armenians, distinguished itself during the war. Led by Major General, it fought in the Battle of Berlin and entered Berlin. Many Armenian soldiers also served in two other multi-ethnic divisions. They came not only from Soviet Armenia, but also from the other Soviet republics and other countries with considerable Armenian minorities.

The Armenian SSR provided weapons and rebuilt broken airplanes. Workers donated to the Defense Fund 216,000,000 rubles. Armenia, as a gift, sent to the front 45 wagons of provisions. Armenian communities in the Middle East and the West also donated considerable sums of money to the Soviet government to help construct a series of tanks for the Red Army. These tanks were named after David of Sasun, the hero of an Armenian medieval epic, and Marshal Bagramyan.

Outside of Armenia and the Soviet Union, Missak Manouchian was one of the leaders of the French Resistance. He was captured and executed by the Nazis in 1944, together with over 20 members of FTP-MOI Paris region led by Manouchian, and remains a much respected figure in modern French history. Decorated solders who fought in the United States Army include Ernest H. Dervishian (recipient of the Medal of Honor), Harry Kizirian (most decorated serviceman from Rhode Island and one of the most decorated marines of the war), and Victor Maghakian (one of the most decorated American soldiers of the war). Brothers Noel Agazarian and Jack Agazarian both served in the British Royal Air Force, Noel was promoted to Flying Officer and participated in the Battle of Britain before being killed in action in 1941, while Jack also became a field agent for the Secret Intelligence Service and was captured and executed in 1945. Their sister, Monique Agazarian, became one of only 10 young women accepted into the Air Transport Auxiliary for ab initio pilot-training.

Gevork Vartanian was an intelligence agent responsible for thwarting Operation Long Jump, and thus preventing the assassination of Joseph Stalin, Winston Churchill, and Franklin D. Roosevelt at the Tehran conference in 1943.

On the Axis side, the Armenische Legion was created within the Wehrmacht, which consisted mainly of Soviet prisoners of war, who had opted to fight for German forces rather than be sent to the Nazi POW camps or killed. The legion was led by former Defence Minister of Armenia General Drastamat Kanayan, who fought against the Soviet Union on the Eastern Front. Kanayan was among the minority in the legion who volunteered, under the hope of freeing Armenia from Soviet control. The total number of Armenians serving in the German armed forces during the war reached 33,000: 14,000 were placed in field battalions, while another 7,000 served in logistical and other non-combat units. The legion participated in the occupation of the Crimean Peninsula and the Caucasus. It did not take part in the Holocaust, on the contrary several Jewish soldiers captured as POWs were saved by some of the Armenians in the Legion. Several instances included Jews being sent to the battalion to evade detection by the Nazis. Towards the end of the war, many of the legion deserted, defected or revolted. In spite of Nazi Germany acknowledging the Armenians were an Indo-European (or Aryan) people, Adolf Hitler personally stated, "I don't trust the Armenians."

There are still some 9,000 veterans of the war who live in Armenia.

Australia
Australia was among the first countries to announce it was at war with Germany, on 3 September 1939. However, Australia did not make a separate declaration of war. The Prime Minister, Robert Menzies considered that the British declaration legally bound Australia, and he announced that a state of war now existed between Australia and Germany as a direct consequence of the British declaration.

More than one million Australian men served in the war out of a total population of around seven million. Although it was ill-prepared for war, the Australian government had soon dispatched Royal Australian Air Force squadrons and personnel to serve with the Royal Air Force. The Royal Australian Navy (RAN) commenced operations against Italy after its entry into the war in June 1940. Later that year the Australian Army entered campaigns against Italy and Germany in North Africa and Greece. German submarines and raiding ships operated in Australian waters throughout the war. The most intensive and numerically largest part of Australia's war effort came after the outbreak of hostilities with Japan in late 1941. The Australian mainland came under direct attack for the first time in 1942, when Japanese aircraft launched a major bombing attack on Darwin in February, and attacked many other towns in northern Australia. Axis covert raiding ships and submarines struck at shipping and shore targets around Australia, including a submarine attack on Sydney Harbour.

For the remainder of the war, the Australian war effort was concentrated in south-east Asia and the South West Pacific Area: they were involved from January 1942 in Malaya, the Dutch East Indies and the Australian territory of New Guinea. During mid-1942 Militia troops fought a stubborn rearguard action in the trying conditions of the Kokoda Track. The bitter and deadly New Guinea campaign came to occupy the attention of most of the Australian armed forces until 1945. Later that year, as the war drew to a close, Australian forces led the campaign to retake Borneo.

Austria
Austria became a full part of Nazi Germany in 1938 among popular acclaim during the Anschluss. About 1.2 million Austrians served in all branches of the German armed forces during World War 2. After the defeat of the Axis Powers, the Allies occupied Austria in four occupation zones set up at the end of World War II until 1955, when the country again became a fully independent republic under the condition that it remained neutral. The four occupations zones were French, American, British, and Soviet, with Vienna also divided among the four powers. This paralleled the situation in post-war Germany.

Azerbaijan
During World War II, Azerbaijan was part of the Soviet Union as the Azerbaijan Soviet Socialist Republic. The capital of Azerbaijan, Baku ranked as the largest centre for the production of oil industry equipment before World War II. The World War II Battle of Stalingrad was fought to determine who would have control of the Baku oil fields. Fifty years before the battle, Baku produced half of the world's oil supply. By the end of 1941, hundred of thousands of Azerbaijanis had joined the People's Voluntary Corps. Azeri Major-General Hazi Aslanov was awarded twice Hero of the Soviet Union.

Mobilization affected all spheres of life, particularly the oil industries. A week after fighting began, the oil workers themselves took the initiative to extend their work to 12-hour shifts, with no days off, no holidays, and no vacations until the end of the war. Meanwhile in September 1942 Hitler's generals presented him with a large decorated cake depicting the Caspian Sea and Baku. Baku then became the primary strategic goal of Hitler's 1942 Fall Blau offensive. This offensive was unsuccessful, however. The German army was at first stalled in the mountains of Caucasus, then decisively defeated at the Battle of Stalingrad and forced to retreat from the area, abandoning all hopes for Reichskommisariat Kaukasus. In 1942 Azerbaijan also became the second largest tea producer of the Soviet Army. By the Decree of the Supreme Soviet of the USSR in February 1942, the commitment of more than 500 workers and employees of the oil industry of Azerbaijan was awarded orders and medals.

Like the Georgians and other people of the Caucasus who were upset with Soviet rule, some Azerbaijanis joined the side of Germany. These units included:
 * The Azerbaijani Legion
 * Freiwilligen-Stamm-Regiment 2
 * Azeri Waffen SS Volunteer Formations

Bahrain
The Sheikh of Bahrain declared war on Germany on September 10, 1939.

Belarus
During WWII, Belarus was part of the Soviet Union, as the Byelorussian SSR. Because of the Molotov-Ribbentrop Pact, the Soviet Union was lulled in to a false sense of security, and was invaded June 22, 1941. The Jewish inhabitants were rounded up by Einsatzgruppen, and slaughtered. Belarus was reclaimed during Operation Bagration in the August of 1944.

Belgium


Belgium declared its intention to remain neutral in the event of war in the lead up to the conflict. In May 1940, Germany launched a surprise attack during its wider invasion of France, and although Belgian forces resisted the German invasion for 18 days, on 28 May 1940, the Belgian army and its commander, King Leopold III, officially surrendered. The King, and much of his army, were incarcerated and remained imprisoned for the rest of the war.

The elected government left for France, and then England, where it established a government in exile based in London and Free Belgian army. The country itself was placed under German military occupation, opposed by the resistance, which lasted until its liberation after September 1944. During the course of the occupation, around 25,000 of Belgium's Jewish community were exterminated.

The Belgian Colonial Empire, notably the Belgian Congo, remained loyal to the Allies despite the surrender and played an important role as an economic asset, producing large amounts of important raw materials. Congolese troops also fought the Italians in East Africa.

Bolivia
Bolivia was one of many Latin American countries to declare war on Germany later on in the war, joining the Allies on 7 April 1943. It was the only country to declare war in 1943. Shortly after war was declared, the President of Bolivia, Enrique Peñaranda, was overthrown in a coup. The new ruler, Gualberto Villarroel, had fascist and anti-Semitic leanings, but foreign pressure compelled him to remain at war and to suppress his more extreme pro-Nazi supporters. Bolivian mines supplied needed tin to the Allies, but with no coastline, the landlocked country did not send troops or warplanes overseas.

Brazil
Brazil was under the dictatorship of Getúlio Vargas and maintained its neutrality until August 1942. There were several German submarine attacks against Brazilian ships between February and August that year in the Atlantic Ocean reaching 1,079 casualties. In response, the Brazilian government, pressured by a population sided with the Allies, declared war against Germany and Italy on 22 August 1942.

Brazil had to be coaxed to enter the war on the side of the Allies. The Allies (United States) built several airfields on Brazilian soil with the understanding that shortly after the war ended, these same airfields would be turned over to Brazil. Also at the outbreak of the war, only Germany and Italy provided any sort of scheduled airline flights to Brazil. The United States was in the unenviable position of agreeing for these flights to continue until such time as these airfields were constructed and the United States started airline flights to Brazil. This also included supplying the Axis Powers with high octane gasoline so the Axis flights could continue until American flights in and out of Brazil could begin. Brazilian naval forces helped to patrol the South and Central Atlantic Oceans, combating Germany's U-boats and commerce raiders. Northeastern Brazil hosted at Natal the largest single American air base outside of its own territory, and at Recife, the U.S. Fourth Fleet. This air base gave support to the North Africa campaign, and a route for USAAF airplanes to fly to India and China.

In 1944, Brazil sent the 25,700-man Brazilian Expeditionary Force (FEB) to fight in Europe, thus becoming the only South American nation (and, along with Mexico, one of two Latin American nations) to send troops overseas. This force joined the U.S. Fifth Army under American general Mark Clark in Italy, and it participated in the Italian campaign until the end of war. In the Italian city of Pistoia (Tuscany) there is a cemetery dedicated exclusively for the Brazilian soldiers who died in WW II. Altogether, over 14,000 Germans soldiers were captured or surrendered to Brazilian Expeditionary Forces. Brazil also sent two Brazilian Air Force groups (one of them a fighter group flying American-built Thunderbolts P-47's) to Italy, becoming the only South American country to send air force units to fight overseas.

The Brazilian Navy as well as the Brazilian Air Force (FAB) were also engaged in searching and destroying German U-boats in the South Atlantic waters. This was necessary, due to the fact that after declaring war on the Axis, Brazil lost over 65 ships to German U-boats torpedoes. On July 31, 1943, the German U-boat U-199 was sunk by two Brazilian aircraft off the coast of Rio de Janeiro. In the same year, the following German U-boats were also sunk at different places off the coast of Brazil, U-662, U-590, U-164, U-598, U-591, U-128, U-161, and the U-513. After these intense campaigns of 1943, the Brazilian coast became off limits to German U-boats.

Bulgaria
Bulgaria was a German ally, signing the Tripartite Pact on 1 March 1941, their main contribution being transit rights for German units involved against Yugoslavia and Greece. Bulgaria occupied portions of Greece and Yugoslavia to recreate the 19th century boundaries of Greater Bulgaria, but it did not participate in the Invasion of the Soviet Union.

After the Communist-dominated coup d'état of 9 September 1944, and the simultaneous arrival of Soviet troops in the country, the Bulgarian government declared war on Germany. Four Bulgarian armies attacked the German positions in Yugoslavia. An armistice was signed with the Allies in Moscow on 28 October 1944. After the Nazis fled Yugoslav territory, the 1st Bulgarian Army continued its offensive in Hungary and Austria under the command of General Vladimir Stoychev. It withstood the Wehrmacht offensive on the Drava River. Bulgaria's participation in World War II ended when its soldiers met British troops in Klagenfurt, Austria in May 1945.

Canada

 * At the time of World War II, Newfoundland, including Labrador, was not part of Canada. See separate Newfoundland section.

On 10 September 1939, Canada likewise declared war on Germany, the country's first independent declaration of war and the beginning of Canada's participation in the largest combined national effort in its history. Canada's military was active in every theatre of war, though most battles occurred in Italy, Northwestern Europe, and the North Atlantic.

Over the course of the war, 1.1 million Canadians served in the Army, Navy, and Air Force. Of these more than 45,000 lost their lives and another 54,000 were wounded. The financial cost was $21,786,077,519.13, between the 1939 and 1950 fiscal years. By the end of the War, Canada had the world's fourth largest air force, and third largest navy. As well, the Canadian Merchant Navy completed over 25,000 voyages across the Atlantic. Many Allied pilots trained in Canada during the war. Canadians also served in the militaries of various Allied countries.

By D-Day, 6 June 1944, the landings at Normandy were accomplished by two beachheads made by the American forces at Omaha and Utah, two by British forces, Sword and Gold, and a final one at Juno made by the 3rd Canadian Infantry Division.

During the war Canada was subject to direct attack when German U-boats penetrated its coastal waters and participated in the Battle of the St. Lawrence. It was the first attack on Canadian soil since the Fenian Raids. A lone Japanese submarine also surfaced and shelled a lighthouse at Estevan Point in British Columbia, although it did no damage.

The war had significant cultural, political and economic effects on Canada, including the conscription crisis which affected unity between Canadian francophones and anglophones. However, the war effort not only strengthened the Canadian economy but further established Canada as a major actor on the world stage.

Caribbean Islands
At the outbreak of World War II, the United States assumed Britain's defense responsibilities in the Caribbean. In September 1940, the two countries agreed to the Lend-Lease Agreement (also called the Bases-for-Destroyers Agreement). It involved the loan of forty out-of-date American destroyers in return for leasing, rent free for ninety-nine years, British naval and air bases on five British West Indian islands—the Bahamas, Jamaica, Antigua, St. Lucia, and Trinidad and Tobago—as well as British Guiana, Bermuda, Leeward Islands, Windward Islands, and Newfoundland. The Lend-Lease Agreement was signed formally in London on March 27, 1941. Under its terms, the United States established eleven military bases in the area (and in Bermuda) and quickly transformed five British colonies in the West Indies into outposts of Caribbean defense for use against German submarine warfare. After President Franklin D. Roosevelt designated the Caribbean as a coastal frontier, the Eastern Caribbean became the forward edge of American defense strategy during the war. American strategists at that time referred to the West Indies as "the bulwark that we watch."

The strategic significance of the Caribbean became evident during the war. More than 50 percent of the supplies sent to Europe and Africa from the United States were shipped from ports in the Gulf of Mexico. One year after the Pearl Harbor attack, the United States Caribbean Defense Command reached a total of 119,000 personnel, half of them stationed in Panama to protect the canal from Japanese attack. Although the expected Japanese attack did not come, the Germans inflicted massive damage on shipping in the Caribbean in 1942. German submarines even slipped into the region's small harbors to shell shore targets and to sink cargo ships at anchor. By the end of the year, U-boats operating in the Caribbean had sunk 336 ships, at least half of which were oil tankers, with a total weight of 1.5 million tons.

Ceylon (Sri Lanka)
Ceylon (now known as Sri Lanka), was a British colony and a major Allied naval base. On 5 April 1942, over 300 aircraft from Japanese carriers bombed the island. Winston Churchill called it "the most dangerous moment" of World War II, because the Japanese wished to replicate a grander success of the attack at Pearl Harbor. British ships, however, were moved to Addu Atoll, Maldives Islands, 1,000 km southwest of Ceylon. Nevertheless, the British lost an aircraft carrier, two cruisers, and two destroyers, while the Royal Air Force squadrons on Ceylon suffered severe losses. The British fleet retreated to East Africa until 1944.

The Ceylon Garrison Artillery Regiment was stationed on Horsburgh Island in the Cocos Islands, to defend it from Japanese attack. However, following agitation by the Lanka Sama Samaja Party, the regiment mutinied on the night of 8 May 1942, intending to hand the islands over to the Japanese. The mutiny was suppressed and three of the Ceylonese soldiers became the only British Commonwealth troops to be executed for mutiny during World War II. Bombardier Gratien Fernando, the leader of the mutiny, was defiant to the end.

Following the Cocos Islands Mutiny, no Ceylonese combat unit was deployed in a front-line combat situation, although Supply & Transport Corps troops were used in rear areas in the Middle East. The defences of Sri Lanka were beefed up to three Allied army divisions because the island was strategically important, as a producer of rubber. Rationing was instituted so that Sri Lankans were comparatively better fed than their Indian neighbours, in order to prevent disaffection among the ordinary people. Ceylonese in Japanese-occupied Malaya and Singapore were recruited by the Japanese for the Lanka Regiment of the Indian National Army, to fight against the Allies. While there was a plan to land them in Ceylon to start a guerrilla war, they never actually saw action.

Chile
Initially, Chile chose to remain neutral in the war, having close trading links with Germany. Later in the war, however, Chile distanced itself from the Axis powers, and the Chilean government took steps to dismiss pro-German military officers. Relations with Axis countries were broken in 1943, and in 1945, Chile declared war on Japan, being the last nation to join the war. As with Argentina, by this time the war was almost over.

China
The Republic of China had been fighting Japan intermittently since the 1931 Mukden Incident, when Japan annexed Manchuria. On 7 July 1937, the Marco Polo Bridge Incident led the two countries to full-scale war. Already engaged in war with Japan, as well as enduring a civil conflict between the Kuomintang (KMT, Chinese Nationalist Party) and the Communist Party of China, the Chinese Nationalist Government's full attention was within its borders in resisting the Japanese during the war. However, Generalissimo Chiang Kai-shek still managed to send troops to Britain's aid in Burma, in early 1942. China's participation in the war was also pivotal in a sense that more than 1.5 million Japanese military personnel were sent to China and bogged down. Japanese casualties in China are estimated at 1.1–1.9 million.

While China had rather warm relations with Germany (see Sino-German cooperation), following the Japanese attack on Pearl Harbor, China formally joined the Allies and declared war on Germany on 9 December 1941.

Many of China's urban centers, industrial resources, and coastal regions were occupied by Japan for most of the war. China suffered a large death toll from the war, both military and civilian. The Chinese Nationalist army suffered some 3.2 million casualties, and 17 million civilians died in the crossfire. After the war, China became one of the main victorious countries and gained one of the permanent seats in the United Nations Security Council.

After the war ended, the Chinese Civil War resumed between the Nationalists and the Communists. The Nationalist government, with its military strength greatly reduced and its economy devastated by the war against Japan, was defeated by the Communists in 1949. The Republic of China retreated to Taiwan while the communist People's Republic of China was established on the mainland.

Colombia
After the attack on Pearl Harbor, Colombia broke diplomatic relations with the Axis powers. Colombia provided the Allies with petroleum products. In 1943, the German submarine U-505 destroyed a Colombian schooner, which caused Colombia to declare a "status of belligerency" against Germany on 26 November 1943.

The German ambassador left the country, and measures of control were implemented, including internment of German citizens in designated areas. Photographs and reconnaissance airplanes belonging to the Colombian-German company Scadta, which used to take aerial shots of Colombian and German cities, were also handed to the United States. During the recovery years, Colombia sent Nestle products (coffee, baby food, etc.) and carbon for heating all over Europe.

Costa Rica
Costa Rica joined the Allies on 8 December 1941. The leftist administration of President Rafael Ángel Calderón Guardia was hostile to Nazism and introduced numerous measures to decrease German influence in the country. Costa Rica declared war on Japan the day after the attack on Pearl Harbor, and on Germany and Italy shortly afterwards.

Croatia
The Independent State of Croatia (Nezavisna Država Hrvatska, or NDH) became a member of the Axis on 10 April 1941 and joined the Tripartite Pact on 15 June 1941. The state was technically a monarchy and a de facto Italian-German quasi-protectorate until the Italian capitulation on 8 September 1943, after which it remained a de facto German quasi-protectorate until the German withdrawal near the end of the war. It had a government controlled by the fascist Ustaše movement, which often had little real power outside of the capital, Zagreb. Its military fought alongside Axis troops; mainly on anti-Partisan operations within the NDH. Volunteers from the NDH fought in Wehrmacht formations on the Eastern Front as the 'Croatian Legion' for some time. The Armed Forces of the Independent State of Croatia remained engaged in battle a week after the capitulation of Germany on 8 May 1945 in an attempt to surrender to Allied forces rather than the Yugoslav Partisans. During the war they launched a campaign of genocide against Serbs in Croatia and Bosnia. They also had concentration camps of their own, separate from those of Nazi Germany such as the Jasenovac death camp.

Cuba
Cuba joined the Allies on 8 December 1941, when it declared war on Japan. On 11 December, it also declared war on Germany and Italy. The United States naval station at Guantanamo Bay served as an important base for protecting Allied shipping in the Caribbean, and on 15 May 1943, a Cuban warship sank a German submarine in waters near Havana. Cuba began to plan a conscription program in order to contribute troops, but this had not materialized by the end of the war.

Cyprus
The Cyprus Regiment was founded on 12 April 1940, and made part of the British Army structure. It was mostly volunteers from the Greek and Turkish Cypriot inhabitants of Cyprus, but also included other Commonwealth nationalities. About 30,000 Cypriots served in the Regiment. It included Infantry, Mechanical, Transport, and Pack Transport Companies. Cypriot mule drivers were the first colonial troops sent to the Western Front. They served in France, Ethiopia and Italy carrying equipment to areas inaccessible to vehicles. The regiment served at Dunkirk, in the Greek Campaign (Battle of Greece), North Africa (Operation Compass), France, the Middle East and Italy. In the post war years and prior to its disbandment, the regiment served in Cyprus and the Middle East, including Palestine in 1945–1948. The Regiment was disbanded on 31 March 1950.

Czech Republic
Czechoslovakia was dismembered by Nazi Germany, starting with Neville Chamberlain's Munich Agreement with Hitler in 1938 and the German–Italian Vienna Awards. The Czech part (western) of the country became the so-called Protectorate of Bohemia and Moravia under so-called State-President Emil Hácha, the newly separated Slovak Republic, a Nazi-dependent puppet regime, led by Roman Catholic priest Jozef Tiso was ultimately inserted in Slovakia. Part of southern Slovakia as well as the complete Ruthenia (the former most eastern part of Czechoslovakia) was annexed by Hungary. Zaolzie was annexed by Poland, only to be snatched from them by the Germans 11 months later.

In 1945 the victorious Soviet Union returned Zaolzie to Czechoslovakia. From 1940, a government-in-exile in London under former Czechoslovak President Edvard Beneš was recognized as an Allied power. The Slovak National Uprising, commenced in August 1944, was suppressed by German forces at the end of October; partisans, however, continued fighting in the mountains till the end of the war. In April 1945, the Red Army defeated the Germans and ousted Tiso's government, annexing Carpathia Ruthenia to the USSR.

Denmark
Denmark officially remained neutral from the outbreak of the war. It was invaded without declaration of war as part of Operation Weserübung and occupied by Germany on 9 April 1940, after being overwhelmed in a few hours of fighting.

On 10 May 1940, the British invaded the Danish islands of Iceland and the Faroe Islands. The United States occupied Greenland, a position later supported by the Danish envoy in Washington, Henrik Kauffmann. Iceland, which was later transferred from British to American control, and declared its independence in 1944.

The Danish government remained in office in Copenhagen until 1943 and signed the Anti-Comintern Pact. On 29 August 1943, the government handed in its resignation to the King and dissolved, as a response to German demands for more concessions. Each Permanent Secretary took control of his own ministry. Denmark was now under German military occupation. Civil affairs were handled by SS-general Werner Best.

On 4 May 1945, German forces in Denmark surrendered to the British army. Since the German commander of Bornholm refused to surrender to the Soviet Union, two local towns were bombed and the garrison forced to surrender. Bornholm remained under Soviet control until 1946.

Dominican Republic
The Dominican Republic declared war on Germany and Japan following the attacks of Pearl Harbor and the Nazi declaration of war on the U.S. It did not directly contribute with troops, aircraft, or ships, however 112 Dominicans were integrated into the U.S. military and fought in the war. In addition, 27 Dominicans were killed when German submarines sank four Dominican-manned ships in the Caribbean.

Dutch East Indies
The rich oil resources of the Dutch East Indies were arguably a prime objective of the Japanese military in its attack on the Allies from 7 December 1941. The Royal Netherlands Navy and the Royal Netherlands East Indies Army were part of the American-British-Dutch-Australian Command, until the Allied forces in the Netherlands East Indies were defeated by Japan in March 1942. Some Dutch personnel and ships escaped to Australia, where they continued to fight the Japanese. The Dutch East Indies was occupied by the Japanese for the remainder of the war.

Ecuador
Ecuador was one of several South American nations to join the Allies late in the war (joined against Germany on 2 February 1945), allowing the United States use of Baltra Island as a naval base.

Egypt
Britain had unilaterally recognized the independence of Egypt in 1922, but continued to occupy the country militarily, and dominate its political, and economic affairs. Subsequent to the Anglo-Egyptian Treaty of 1936, the British occupation was limited to the Suez Canal Zone, however, a treaty provision allowed British troops to re-occupy the rest of the country in time of war. The continued presence of British forces on Egyptian territory, and Britain's efforts to divest Egypt of its control over Sudan led to increased anti-British sentiment in the country.

Egypt was seen by both the Allies and the Axis as of vital strategic importance due to the Suez Canal, and its central geographical location in the Arab World. Whilst Egypt remained officially neutral for most of the war, the Egyptian Government engaged in secret negotiations with Germany about the prospect of Egypt joining the Axis should the British be defeated in the Western Desert. Many Egyptian politicians, and army officers, including the future President of Egypt Anwar El-Sadat, sought Axis support for removing the occupying British forces from the country. King Farouk himself corresponded directly with the German Government in Berlin for this purpose.

After British forces, under the command of General Wavell, inflicted a heavy defeat on an initial Italian invasion of Egypt, Germany was compelled to enter the North African theatre to reverse the British successes, and to prevent a complete disintegration of the Italian forces in Libya. A series of German victories under General Erwin Rommel brought Axis forces within 160 kilometres (100 miles) of Cairo, creating great expectation among Egyptian nationalists that a British defeat would spell the end of Britain's occupation of Egypt. Ultimately, however, British Lieutenant-General Bernard Montgomery's victory at El-Alamein heralded the end of Axis advances in Egypt, and the eventual Axis defeat in North Africa. Nonetheless, King Farouk still resisted British pressure to declare war on Germany until 1945. Farouk recounted that, even at this late stage, he had only declared war so as to guarantee Egypt a seat at post-war negotiations.

El Salvador
José Castellanos Contreras was a Salvadoran army colonel and diplomat who, while working as El Salvador's Consul General for Geneva during World War II, and in conjunction with a Jewish-Hungarian businessman named György Mandl, helped save up to 40,000 Jews and Central Europeans from Nazi persecution by providing them with false papers of Salvadoran nationality. From 1931 to 1944, El Salvador was ruled by Maximiliano Hernandez Martinez, an admirer of Hitler and Mussolini. Nonetheless, the dictator declared war on both Japan (8 December 1941) and Germany (12 December 1941) shortly after the attack on Pearl Harbor, due to El Salvador's strong economic ties with the United States. Hernandez removed Germans from the government and interned Japanese, German, and Italian nationals. The Second World War made Salvadorans weary of their dictatorship, and a general national strike in 1944 forced Hernandez to resign and flee to Guatemala, he was later killed in Honduras by a vengeful Salvadoran citizen.

Estonia
The Molotov–Ribbentrop Pact between Germany and the Soviet Union left Estonia in the Soviet sphere of interest. The Soviet Union threatened Estonia with war if Estonia did not agree with the mutual assistance pact, which required allowing the Soviet Union to build military bases into Estonia. Estonian government, convinced that winning a war against the Soviet Union was impossible, agreed on 28 September 1939. The Soviets conducted a coup d'état with support of the Red Army in June 1940, and a sham election was held under Soviet control. The new government took office and the Estonian Soviet Socialist Republic was proclaimed on 2 July 1940. The puppet state was formally accepted into the Soviet Union on 6 August.

Estonia was occupied by Germany in 1941 after war broke out between Germany and the Soviet Union. With the return of the Soviet Armed Forces, 70,000 Estonians joined the German side to fight the Soviets. The National Committee failed to restore the national government in September 1944 due to the Soviet reoccupation. Estonia remained occupied by the USSR until 1991.

Ethiopia
At the outbreak of the war, Emperor Haile Selassie of Ethiopia was in exile in England trying in vain to obtain Allied support for his nation's cause. The Ethiopian Patriots Movement had begun its guerrilla war against the occupying Italian forces the day Addis Ababa fell in May 1936.

Upon the emperor's flight into exile, remnants of Ethiopia's disbanded imperial army had transformed into guerrilla units. Urban city residents throughout the country formed underground movements to aid the Patriots as the overall population led a passive resistance campaign aimed at stifling Mussolini's economic agenda for the region. As a result, the Italians were never able to successfully occupy and secure the entire country including the emperor's relocated capital at Gore in the southwest. Throughout the occupation and into the beginning of the Second World War, the constant harassment of Italian columns and communication and supply lines reduced their fighting capabilities and their morale. A state of paranoia among Italian troops and civilians alike had sunk in as they became increasingly isolated from Rome. Fascist retaliation to Patriot attacks were brutal and often targeted the civilian population, which only further filled the ranks of the Patriots creating a cycle that led to the eventual demise of Mussolini's Italian East Africa.

Britain's declaration of war against Italy reinvigorated the Patriot movement and paved the way for the final ousting of the Italians in Ethiopia and in the Horn of Africa. The Allied liberation campaign of Ethiopia began in the winter of 1940. Emperor Haile Selassie, with the support and cooperation of the British, was transported to the Sudan to work alongside Major Orde Wingate to organize and lead the main Ethiopian Patriot divisions that had fled fascist-controlled Ethiopia upon news of Britain's declaration of war.

The East African Campaign was conducted by a largely multi-African force and consisted of Ethiopian, Eritrean, British, Sudanese, Kenyan, Rhodesian, South African, Indian, Nigerian, Ghanaian and Free French Forces. Within months, the liberation of Ethiopia was achieved, and on 5 May 1941, five years to the day that the Emperor fled his capital, Haile Selassie was restored to his throne. The defeat of fascists in Ethiopia marked the first victory for the Allies in the Second World War and allowed for the remaining forces to be quickly moved up to Egypt to confront the Axis advance towards Cairo.

Fiji
Fiji was a British colony during World War II. The Fiji Defence Force served with New Zealand Army formations, under the Allied Pacific Ocean Areas command. The Fiji Infantry Regiment fought in the Solomon Islands Campaign.

Finland
Finland was left to the Soviet sphere of interest in Molotov–Ribbentrop Pact, and when it refused to allow the Soviet Union to build bases on its territory, it was attacked by Soviet forces in the Winter War (30 November 1939 – 13 March 1940). After the war, Finland unsuccessfully sought protection from the United Kingdom and from Sweden to counter the continuing Soviet pressure, before turning to improving relations with Nazi Germany. This produced cooperation between the countries, which led three days after the start of Operation Barbarossa to a Soviet pre-emptive air attack on Finland, which started the Continuation War (25 June 1941 – 4 September 1944), in which Finland was a co-belligerent of Germany. The UK and Canada declared war on Finland on 6 December 1941, but the United States never did so.

To secure military support needed to stop the Vyborg–Petrozavodsk Offensive coordinated with D-Day, the Ryti-Ribbentrop Agreement was signed on 26 June 1944, in which Finnish and Nazi German relations became closest to an alliance. An armistice was signed after the Soviet offensive was fought to a standstill, and the Wehrmacht was retreating from the Baltic states. The treaty required Finland to expel all German troops, which led to the Lapland War (15 September 1944 – 25 April 1945). This was shortly before the complete surrender of Nazi forces all over Europe on 7–8 May 1945 (V-E Day). Complete peace with the UK and the USSR was concluded in the Paris Peace Treaties, 1947.

France
France was one of the original guarantors of Polish security and as such was one of the first countries to declare war on Germany. In 1940, following the Battle of France, the French government signed an armistice with Germany, leading to the foundation of Vichy France and Free French Forces in exile. The leader of the Free French, Charles de Gaulle, took control of France in 1944 and the country ended the war as an ally.

Free French Forces
The Free French Forces (FFF) of the French Committee of National Liberation (CFLN), a London-based exile group led by Charles de Gaulle, were formed in 1940 to maintain the French commitment to the Allies and liberate French territory occupied by Germany. Together with the French Resistance, they played a part in the Mediterranean Theatre and the liberation of western Europe, including France in 1944. By 1943, free France had a vast land (but no war industry, it remained dependent on US aid) and then changed its name into fighting France (which regrouped the Free French, the Vichy authority that joined it and the interior resistance) with a sort of government, the CFLN, which officially became French government in June 1944 and took control of France in August and September 1944.

In 1944, the FFF soldiers were about 560,000. In 1945, more than 1,300,000. The Resistance (forces of the interior), according to D. E. Eisenhower, played a role equal to 15 fighting divisions. The FFF and Resistance played a major role during the liberation of France. The first Allied unit on the Rhine was a free French unit, the RICM.

Vichy France
When France signed armistice agreements with Germany and Italy, the country was split into two parts, an occupied sector, and an unoccupied sector, in which a new government led by Marshal Philippe Pétain was located in the spa town of Vichy, hence the name Vichy Regime. It remained officially neutral during the conflict but was forced into widespread collaboration with Germany. Prime Minister Pierre Laval repeatedly sought to bring France closer to the Axis side, but was vetoed by Pétain. On several occasions Vichy forces were attacked by British and Free French forces during the war, most notably at the Battle of Dakar, the invasion of Syria in 1941, during landings in French North Africa in November 1942 and the Madagascar campaign of 1942. As a result of Vichy North Africa violating the terms of the 1940 armistice by calling a cease-fire following Operation Torch, the Germans occupied all of continental France in the fall of 1942 but allowed the Vichy government to continue operating. Vichy North Africa's government and military led by François Darlan joined the Allies. After Darlan was assassinated, de Gaulle finally took power alongside Henri Giraud. Laval was executed for high treason after the war.

Georgia
Reaching the Azerbaijan oilfields became one of the main objectives of Hitler's invasion of the Soviet Union. But the armies of the Axis powers never got as far as the Georgian Soviet Socialist Republic (Georgian SSR). The Georgian SSR contributed almost 700,000 officers and soldiers (about 20% of the total 3.2–3.4 million citizens mobilized), out of which 300,000 were killed. 137 Georgians were awarded Hero of the Soviet Union having the most numerous recipents of this award in the Caucasus. It was also a vital source of textiles as well as one of the most important manufacturers for warplanes of almost all Soviet types, including the Yak-3, LA-5 and the LaGG-3.

Aside from Joseph Stalin, General Alexi Inauri and Lavrenti Beria, Georgians contributed to the war effort. Some were high-ranking Polish officers, such as Zakaria Bakradze and Valerian Tevzadze, who took part in the defence of Warsaw, left their homeland after the Red Army invasion of Georgia in 1921. Those who survived the Katyn massacre, joined local Polish underground groups to continue fighting the Nazis. More than 1,000 Georgians were officers in the Polish army, only a few survived after the Warsaw uprising. Jerzy Tumaniszwili was promoted to Admiral of the Polish Navy in 2009.

Vasilij Shalvovich Kvachantiradze was a famous Soviet sniper who trained alongside Zaytzev and killed many German officers and soldiers.

Dimitri Amilakhvari was a Lieutenant Colonel of the French Foreign legion and a vital figure for the French resistance against German occupation forces. Known as "Bazorka" by the French population, he fought on many fronts and was posthumously awarded with the Legion of Honor after being killed in action during the Second Battle of El Alamein. Before he died, he was also awarded with Ordre de la Libération from Charles de Gaulle and the Norwegian War Cross. After the heroic stand at the Battle of Bir Hakeim, de Gaulle named Amilakhvari and his legionaries the "Honour of France"

Around 30,000 volunteers and emigrants, but also captured Georgian Soviet soldiers chose to fight for the Germans, in such units as:
 * Georgische Legion (Georgian volunteers but also included volunteers from other peoples of the region)
 * Freiwilligen-Stamm-Regiment 1 (Georgians volunteers)
 * SS-Waffengruppe Georgien (Georgian volunteers)
 * I. Sonderverband Bergmann Battalion (Georgian volunteers)

There were different reasons why these people joined the Axis. The captured Soviet soldiers were forced to switch sides, unless they wanted to get killed or end up in labor camps. Everyone who volunteered, did so because of Hitler's promise, that Georgia would become independent again from the Soviet Union and also allowed to redraw its old border lines, in case of Axis victory. That would have caused Georgia to become two times the size than it was.

One Georgian battalion in the Netherlands (822nd Infantry Battalion) staged what is described as Europe's last battle of World War II. This event was the Georgian Uprising of Texel. When it became clear that the Germans were losing, the collaborationist Georgians of the "Queen Tamar" Battalion decided to switch sides. On 6 April 1945, more than 400 German officers and soldiers were killed silently in their quarters and on patrol. After the failed attempt of the Georgians to take the heavily fortified coastal batteries still manned by surviving German forces, a heavy counterattack led to fierce fighting between the two parties. 565 Georgians, 117 Dutch inhabitants, and about 800 Germans died during this battle.

Germany
Nazi Germany, led by Adolf Hitler, was the primary Axis Power in the European Theatre. The surrender of the German forces between 4 May and 8 May 1945, signaled the end of the war in Europe.

Gibraltar
The British overseas territory of Gibraltar has been a British fortress and bulwark for over 300 years. From the first days of World War II, the Rock became a pivot of the Mediterranean, Operation Torch, the invasion of North Africa, was coordinated from the Rock. Operation Tracer, a top-secret mission in which six men were to be buried alive inside the Rock of Gibraltar so that they could monitor enemy movements if the Rock was captured.

Greece
Greece dealt the first victory for the Allies by resisting the Italian invasion on 28 October 1940 and pushing Mussolini's forces back into Albania. Hitler was reluctantly forced to send forces to bail out his ally and subdue Greece (Operation Marita). The resulting Battle of Greece in April 1941 may have delayed the invasion of the Soviet Union by six weeks, and the heavy losses of the German Fallschirmjäger over Crete effectively put a halt to large-scale German airborne operations for the remainder of the war.

The country was occupied by Germany, Italy and Bulgaria, while the government and the King fled the country to Egypt, from where they continued to fight alongside the Allies. Inside the occupied country, the Axis installed a series of puppet governments, which commanded little allegiance from the population and had little real authority. A vigorous Resistance movement developed from 1942 on, dominated largely by the leftist National Liberation Front (EAM).

Throughout 1943, the guerrillas succeeded in liberating much of the country's mountainous interior, establishing a free zone called "Free Greece". After the Italian capitulation in September 1943, the Germans took over the Italian zone, often accompanied by bloodshed and atrocities, as the Italians tried to resist (as in Cephallonia), or as the Allies tried to occupy Italian-held areas (the Dodecanese Campaign). As the tide of the war turned, and Liberation approached, the Resistance became divided along political lines, and a mini civil war ensued between EAM, rightist resistance groups and the collaborationist government's Security Battalions. An agreement establishing a national unity government was reached in the May 1944 Lebanon conference, which eased tension somewhat in the final months of the Occupation.

With the advance of the Red Army through Eastern Europe in summer 1944, the German forces withdrew from the Greek mainland in October–November 1944, although garrisons were left behind in many islands, including Crete, where the German forces surrendered after the unconditional surrender on 8 May 1945. The returning government in exile, backed by British forces, soon clashed with EAM forces in Athens, in the first episode of the Greek Civil War; a conflict that would last until 1949 and leave a divisive legacy in Greek politics and society until the 1970s.

Guatemala
Guatemala initially stayed out of World War II, with President Jorge Ubico declaring the country's neutrality on 4 September 1941. This pronouncement was reinforced five days later with another declaration. Ubico implemented strong prohibitions on Nazi propaganda in Guatemala, which had one of Latin America's largest German immigrant populations. Later, Guatemala moved into the Allied camp—on 9 December 1941, it declared war on Japan, and three days later, it declared war on Germany and Italy.

Guernsey
The Channel Islands are self-governing British dependences, off the French coast and were the only British territory occupied by Germany. They were occupied by German forces after the fall of France and after British forces had been withdrawn. Strong German defences were set up, but the islands were not assaulted, except by occasional hit-and-run commando raids. German forces surrendered at the end of the war. Almost all the Jewish people fled the islands before the German occupation; those who remained were deported to extermination camps.

Haiti
Haiti remained neutral in World War II until the bombing of Pearl Harbor, declaring war on Japan the day after the attack, and on Germany and Italy shortly afterwards. Haiti gave food supplies to Allied forces and hosted a detachment of the United States Coast Guard but did not contribute troops, however five Haitians from the Haitian Air Force were integrated into the U.S. military (Tuskegee Airmen division) and fought in the war. The President of Haiti, Élie Lescot, introduced several unpopular emergency measures during the war, which critics claimed were designed to increase his power. Lescot was deposed the year after the war ended.

Honduras
Honduras was initially neutral in the war but joined the Allied side after the attack on Pearl Harbor. It declared war on Japan on 8 December 1941, and on Germany and Italy five days later. It contributed food and raw materials to the Allied war effort but did not send troops.

Hong Kong
Hong Kong was under the jurisdiction of the British but came under the control of the Japanese after the gruelling Battle of Hong Kong drew to a close on Christmas Day of 1941. The territory was liberated in 1945.

Hungary
Hungary was a significant German ally. It signed the Tripartite Pact on 20 November 1940, and joined in the invasion of the Soviet Union the next year. When, in 1944, the government of Regent Miklós Horthy wished to sign a ceasefire with the Allies, he was overthrown by the Nazis and replaced by a government run by the fascist Arrow Cross movement, which ruled the country until it was overrun by the Soviets.

Iceland
Iceland was a free state at the outbreak of war in personal union with the King of Denmark acting as head of state. After the invasion of Denmark by German forces, Iceland lost all contact with the King. Following this, British forces invaded neutral Iceland on 10 May 1940, to secure bases for themselves and to deny Germany the same option. Though most of Reykjavík's modest police force was absent, preparing for a potential German landing, a small armed force was present, but obeyed orders not to resist the British. The British proceeded to arrest a number of German nationals, including the German consul, Werner Gerlach. They also seized radio and telephone services, and blocked roads leading into Reykjavík, isolating the city from the rest of the country.

Iceland's government formally protested the occupation, on the grounds of neutrality and national sovereignty, but it provided the British with de facto cooperation. During the height of the occupation, 25,000 British soldiers were stationed in Iceland, compared to roughly 40,000 inhabitants of Reykjavík. On 7 July 1941, control of Iceland was transferred from Britain to the USA, as British troops were needed more urgently elsewhere. The U.S. was not yet at war, but had established a defense zone and Neutrality patrols in the Western Atlantic. Iceland needed to be denied to the Germans, and it provided valuable air and shipping bases to the American Air Force, Navy, and Merchant Marine.

Iceland experienced an economic boom during the occupation, since many Icelanders took jobs working for the foreigners, and some say that bretavinnan (roughly, the British Jobs) provided some of the successes of the post-war Icelandic economy. On 17 June 1944, with American encouragement, Iceland became a permanently independent republic, and it cut all ties with Denmark. Despite being occupied by Allied forces starting in 1940, Iceland remained officially neutral throughout the duration of the Second World War. Iceland did provide important air bases and naval facilities to the Allies. Icelandic air bases such as at Keflavík were important to the Allied fight against the German U-boats in the Battle of the Atlantic.

With its small population, Iceland was in no position to raise any armed forces. The close cooperation between the Americans and the Icelanders led to Iceland's giving up a position of neutrality and becoming a charter member of the North Atlantic Treaty Organization (NATO) in 1949. Iceland has not had any armed forces (but see "Cod Wars"), but its contribution was bases for its allies: the American Air Force Base and Naval Air Station at Keflavík. Iceland was also a vital link in the SOSUS anti-submarine network.

India
The Indian Empire (consisted of areas covered by present-day India, Pakistan, Bangladesh, and Burma), controlled by Britain during the war, was covered by Britain's declaration of war. On 12 September 1939, the Upper House of the Central Legislature of India sent a formal message of admiration to Poland. On the same day, the Aga Khan placed his services at the disposal of the Government of India.

The 5th Infantry Division of India fought in the Sudan against the Italians before being moved to defend Libya against the Germans. The Division was then moved to Iraq to protect the oilfields. After this the division was moved to the Burma front, together with eight other Indian Divisions, and then occupied Malaya. It was finally moved to Java to disarm the occupying Japanese garrison. The 4th Infantry Division of India fought in North Africa, Syria, Palestine and Cyprus before being sent into Italy. Together with the 8th and 10th Divisions it participated in the taking of Monte Cassino, after which it was moved to Greece. India also provided the Allies with assault and training bases, and provided huge quantities of food and other materials to other Commonwealth forces, and to people on the British home front.

Over 6.8 million Indian citizens fought with the Indian Army, Royal Indian Air Force, and Royal Indian Navy, forming the largest army raised by voluntary enlistment. Part of India was occupied by Japanese forces during the war, and India suffered 1.5 million to 4 million civilian dead from famine in the Bengal region, as a result of circumstances resulting from the Japanese invasion of Burma. Over 96,000 Indian members of the armed forces were killed or went missing in action, and 74,354 were wounded during the war. Indian personnel received 2,000 awards for gallantry, including 31 Victoria Crosses.

Some Indian nationalists used the opportunity of war as a time to fight the British. This led to considerable forces of Indians who decided to fight on the Axis side against the British, mostly POW's captured in Singapore. About 40,000 Indians fought on the side of the Japanese in the Indian National Army, and about 1,000 more were recruited by Nazi Germany for the Tiger Legion.

Andaman & Nicobar Islands
On 23 March 1942, Japanese forces invaded the Andaman and Nicobar Islands. In December 1943, the Japanese-sponsored Free India Movement (Provisional Government of Free India) was formed. The Andaman Islands were renamed Shaheed Islands, and the Nicobars were renamed Swaraj Islands. Andaman & Nicobar Islanders fought alongside the Japanese during this time. The islands were not reoccupied by the British until 6 October 1945.

Indonesia

 * See Dutch East Indies

Iran
During the start of the war the Allies demanded that Iran remove German nationals from Iran fearing they might be Nazi spies or harm the British-owned oil facilities, but Reza Shah refused, stating that they had nothing to do with the Nazis.

German demand for oil rose and the Allies worried that Germany would look to neutral Iran for help. Soon the Allies questioned themselves about Iranian neutrality and they gave Reza Shah a final warning to remove the German workers. He refused once again. In August 1941, the British and Soviet troops invaded Iran (Operation Countenance) and, in September 1941, forced Reza Shah Pahlavi to abdicate his throne. He was replaced by his son Mohammad Reza Shah Pahlavi, who was willing to fight the Axis powers. Within months Iran entered the war on the side of the Allies and became known as "The Bridge of Victory".

Iran's geographical position was also important to the Allies. It provided a 'blue water' supply route to the Soviet Union via the port of Bandar Abbas and a specially constructed railway route. The supply routes were known collectively as the Persian Corridor. Soviet political operatives known as "agitprops" infiltrated Iran and helped establish the Comintern affiliate Tudeh Party in early in 1942.

By January 1942, the United Kingdom and the Soviet Union agreed they would end their occupation six months after the war's end.

The Soviet Union fomented revolts among the Azerbaijani and Kurdish peoples in Iran and soon formed the People's Republic of Azerbaijan in December 1945 and the Kurdish People's Republic not long after, both being run by Soviet-controlled leaders. However, Soviet troops remained in Iran, following the January 1946 expiration of a wartime treaty providing for the presence of American, British and Soviet troops in Iran during the war.

Iraq
Iraq was important to Britain through its position on a route to India and the strategic oil supplies that it provided. After the ejection of the Ottoman Turks at the end of the First World War, these were protected by a significant Royal Air Force base at Habbaniya and the maintenance of sympathetic governments. Because of the United Kingdom's weakness early in the war, Iraq backed away from its Anglo-Iraqi Alliance with the country. When the British High Command requested to send reinforcements to Iraq, the country's Prime Minister, Nuri-es Said, allowed a small British force to land. Consequently he was forced to resign after a pro-Axis coup under Rashid Ali in April 1941. Later British requests to reinforce Iraq were denied by the new leadership.

The new regime secretly began negotiations with the Axis Powers. The Nazis responded quickly and sent military aid by Luftwaffe aircraft to Baghdad via Syria. Indian troops consequently invaded in late April 1941 and reached Baghdad and RAF Habbaniyah in May. The Iraqi army attacked Habbaniyah but quickly capitulated and Rashid Ali fled the country. The United Kingdom forced Iraq to declare war on the Axis in 1942. British forces remained to protect the vital oil supplies. British and Indian operations in Iraq should be viewed in conjunction with events in neighbouring Syria and Persia.

Ireland
Independent Ireland remained neutral, the only member of the British Commonwealth to do so. (Northern Ireland, as part of the United Kingdom, fought on the allied side.) Irish citizens were free to work abroad and join foreign militaries. "In January 1942 it was found that in the whole of the British Army 23,549 men (0.05%) were born in Ireland and 28,287 in Northern Ireland ... In 1944 the Ireland figure had increased to 27,840 and that for Northern Ireland had reduced to 26,579." By the end of the war the figures concluded that 50,000 men and women born in the southern Irish Free State served in the British armed forces, although this estimate has risen considerably over the years.

In June 1940 British Major General Bernard Montgomery was tasked to make plans to invade Ireland in order to seizure Cork and Cobh. Winston Churchill also to invade to take the three former Treaty Ports.

One particular southern Irishman who joined the British armed forces, to fight the axis, continues to hold a uniquely distinct honor, Brendan ('Paddy') Finucane the youngest Wing Commander and fighter ace in the RAF's history, who, before the age of 22, achieved one of the highest kill rates in the Battle of Britain and in offensive operations over France, shooting down 32 axis planes (23 of which were Bf 109s) in his shamrock crested spitfire.

A total of roughly forty Irish people were killed in the Bombing of Dublin in World War II and County Carlow in apparently-accidental bombings by the Luftwaffe. The bombings have been cited as the result of either deliberate attacks, errors in navigation or British electronic countermeasures against the Luftwaffe.

The decision to go ahead with the D-day landings was decided by an Atlantic ocean weather report from Blacksod Bay, County Mayo Ireland.

Isle of Man
The Isle of Man is a self-governing Crown dependency external to the United Kingdom. Its foreign relations and defense, however, are the responsibility of the government of the UK. During the Second World War the Isle of Man had a detention camp for Axis citizens and suspected sympathisers, including members of the British Union of Fascists and the Irish Republican Army. A naval base, radar network and training stations were also established on the island.

Italy
Italy had completed conquests (Ethiopia and Albania) prior to its entry into World War II. After the initially successful campaigns of Nazi Germany, Italy join in the war in June 1940, planning to get a share of Allied territory with the defeat of France. Italy's war effort went poorly, resulting in defeats in Greece and North Africa. The Allies started to invade Italy in the summer of 1943 and Mussolini's government collapsed. The new royal government of Marshal Pietro Badoglio signed an armistice with the allies, but most of the country was quickly occupied by the Germans, who established a puppet government under Mussolini in the north, the Italian Social Republic (also known as the Salò Republic, from its headquarters). Badoglio and the king escaped to Brindisi without giving any order to the army, which was left in chaos and without leadership: some divisions surrendered to the Germans, other fought back on their own. The royal government remained in control of the south and declared war on Germany; the military forces it still controlled joined the Allies in a position of co-belligerence. It was eventually re-established as the government of all of Italy shortly before the end of the war in the spring of 1945, when partisan uprisings liberated northern Italy. Italy would become a member of NATO after the war, but lost the region of Istria and the Dalmatian city of Zadar to Yugoslavia, and all its colonies excluding Somalia.

Japan
Japan was the leader of the Axis powers in the Pacific Theatre. Some people consider that World War II actually began with the invasion of China by Japan. The war ended with the capitulation of Japan after the atomic bombings of Hiroshima and Nagasaki by the US. Although the US saw most action in the Pacific Theatre, the Soviet Union and United Kingdom also had a role in Japan's defeat.

Jersey
The Channel Islands are self-governing British dependences, off the French coast and were the only British territory occupied by Germany. They were occupied by German forces after the fall of France and after British forces had been withdrawn. Strong German defences were set up, but the islands were not assaulted, except by occasional hit-and-run commando raids. German forces surrendered at the end of the war. Almost all the Jewish people fled the islands before the German occupation; those who remained were deported to extermination camps.

Korea
Korea was under Japanese rule as part of Japan's 50-year imperialist expansion (22 August 1910 ~ 15 August 1945). Formally, Japanese rule ended on 2 September 1945 upon the Japanese defeat in World War II in 1945.

During World War II more than 100 000 Koreans were mandatorily drafted into the Imperial Japanese Army.

After the surrender of Japan to the allied forces on August 15, 1945, Korea was jointly occupied by Soviet and American forces, with political disagreements leading to the separation of the peninsula into two independent nations. This eventually escalated into the Korean War.

Laos
In 1945 the Japanese occupied Vientiane in April. King Sīsavāngvong was detained by the Japanese, but his son Crown Prince Savāngvatthanā called on all Laotians to resist the occupiers.

Prince Phetxarāt, however, opposed this position, and thought that Lao independence could be gained by siding with the Japanese, who made him Prime Minister of Luang Phrabāng, though not of Laos as a whole. In practice the country was in chaos and Phetxarāt's government had no real authority. Another Lao group, the Lao Sēri (Free Lao), received unofficial support from the Free Thai movement in the Isan region. Thailand re-annexed a small portion of Laos following the conclusion of the French–Thai War in 1941. The territories were only returned to French sovereignty in October 1946.

Latvia
After the conclusion of Molotov–Ribbentrop Pact, Latvia was compelled to accept Soviet garrisons. On 16 June 1940, threatening an invasion The Soviet Union issued an ultimatum demanding that government be replaced and that unlimited number of Soviet troops be admitted. Knowing that the Red Army had entered Lithuania a day before, and that its troops were massed along the eastern border and mindful of the Soviet military bases in Western Latvia, the government acceded to the demands, and Soviet troops occupied the country on June 17. On August 5, 1940, following mock parliamentary elections, Latvia was annexed into USSR. The following year, August 1940 to June 1941 is known as the Year of Terror in Latvia; USSR security agencies "Sovietized" Latvia, in the process killing or deporting to their deaths in slave labor camps between 35,000 and 50,000 residents of Latvia.

After the outbreak of German-Soviet hostilities, Soviet forces were quickly driven out of the territory of Latvia by German forces, with Riga being liberated from the Soviets on 1 July 1941 (eight days after the start of hostilities). Initially, the German forces were almost universally hailed as liberators, but Nazi occupation policies gradually changed that. With the gradual defeat of the German Armies on the Eastern Front, the Red Army started reoccupying Latvia in the late summer of 1944. Riga was retaken by Soviet forces on 13 October 1944, and a major part of the German Army Group North (Heersgruppe Nord) was cut off in Kurzeme, the peninsula that forms the northwestern part of Latvia. There they locally raised Latvian units formed the "Kurland Fortress", which successfully held out until the end of the war and only surrendered because it was ordered to by Admiral Donitz as part of the overall German surrender. Both occupation powers recruited volunteers and drafted conscripts for their armies from the local population, but for both practical reasons and the staunchly anti-communist inclination of the population, the vast majority of men fought on the Axis side.

The Latvian Waffen SS Volunteer Legion was officially formed on 16 March 1943, but the first Latvian Security Police Battalions had been formed more than a year earlier. Despite the word "volunteer" in the name of the Legion, the German Occupation Government soon resorted to conscription to increase it size, and Latvia became one of two countries (the other was Estonia) from where the Waffen SS soldiers were draftees. By 1 July 1944, more than 110,000 men were under arms in German controlled units. The Latvian Legion consisted of 87,550 men, of them 31,446 serving in the combat units that were directly part of the Waffen SS (the 15th and 19th Waffen-Grenadier Divisions), 12,118 in Border Guard regiments, 42,386 in various Police Forces, and 1,600 in other units. 22,744 men served in units outside Legion such as Wehrmacht Auxiliaries. On 12 September 1950, Harry N. Rosenfield, the United Nations Refugee Relief Association Commissioner, wrote the following to Latvian Ambassador J. Feldmanis, minister plenipotentiary, chargé d'affaires of Latvia: "That the Baltic Waffen SS. Units (Baltic Legions) are to be considered as separate and distinct in purpose, ideology, activities, and qualifications for membership from the German SS, and therefore the Commission holds them not to be a movement hostile to the Government of the United States under Section 13 of the Displaced Persons Act, as amended." Some Latvian personnel took an active part during the Holocaust, working as part of both the Soviet and the Nazi occupation governments.

Lebanon
Lebanon, then under French rule was controlled by the Vichy government after the fall of the French Third Republic. Lebanon was invaded and occupied by Allied forces from Palestine during the Syria–Lebanon Campaign. De Gaulle declared Lebanon independent on 22 November 1943. In 1945, Lebanon declared war on Germany and Japan.

Liberia
Liberia granted Allied forces access to its territory early in the war. It was used as a transit point for troops and resources bound for North Africa, particularly war supplies flown from Parnamirim (near Natal) in Brazil. Perhaps more importantly, it served as one of the Allies' only sources of rubber during the war; the plantations of Southeast Asia had been taken over by the Japanese.

The importance of this resource led to significant improvement of Liberia's transport infrastructure and a modernisation of its economy. Liberia's strategic significance was emphasised when Franklin Roosevelt, after attending the Casablanca Conference, visited Liberia and met President Edwin Barclay. Despite its assistance to the Allies, Liberia was reluctant to end its official neutrality and did not declare war on Germany until 27 January 1944.

Liechtenstein
Shortly following the end of World War I, Liechtenstein concluded a customs and monetary agreement with neighboring Switzerland. In 1919, the close ties between the two nations were strengthened when Liechtenstein entrusted Switzerland with its external relations. At the outbreak of war, Prince Franz Josef II, who had ascended the throne only months before, promised to keep the principality out of the war and relied upon its close ties to Switzerland for its protection.

Attempts to sway the government did occur. After an attempted coup in March 1939, the National Socialist "German National Movement in Liechtenstein" was active but small. The organization, as well as any Nazi sympathies, virtually disappeared following the eruption of war.

Lithuania
As a result of Molotov–Ribbentrop Pact between Nazi Germany and the Soviet Union, Lithuania was occupied by the Red Army and forcibly annexed into the Soviet Union along with Latvia and Estonia, with no military resistance. Some Lithuanians sided with Germany after Hitler eventually invaded the Soviet Union in the hopes of restoring Lithuania's independence. Some collaborators were involved in the Holocaust and other crimes against humanity. A Lithuanian division was formed in the Red Army.

Luxembourg
When Germany invaded France by way of the Low Countries in the spring of 1940, Luxembourg, despite its neutrality, was quickly invaded and occupied (despite attempts by the government to slow the advancing German forces), having put up little resistance and immediately surrendering. The Luxembourgeois government went into exile but never declared war on the Axis, and Luxembourg was effectively annexed by Germany. Luxembourg remained under German control until liberated by the Allies at the end of 1944.

Malaya
Malaya was under British rule before the war began. It was occupied by Japan in 1942 through 1945. The Malayan Communist Party became the backbone of the Malayan Peoples' Anti-Japanese Army.

Malta
Malta was a British colony during World War II. The Legislative Council of Malta reaffirmed the people's loyalty to Britain on 6 September 1939. Between June 1940 and December 1942, Malta was one of the most heavily bombed places on earth. Malta became the besieged and battered arena for one of the most decisive struggles of World War II, with some historians calling this battle The Mediterranean Stalingrad. The UK awarded the George Cross to the island of Malta in a letter dated 15 April 1942, from King George VI to the island's Governor William Dobbie: "To honour her brave people, I award the George Cross to the Island Fortress of Malta to bear witness to a heroism and devotion that will long be famous in history".

The fortitude of the population under sustained enemy air raids and a naval blockade, which almost saw them starved into submission, won widespread admiration in Britain and other Allied nations. The George Cross is woven into the Flag of Malta.

Manchukuo
Established in 1931 as a puppet state of Japan, the Empire of Manchukuo was led by Pu Yi, the last Emperor of China, who reigned as Emperor Kang De. The state contributed little to the war but remained a loyal ally to Japan until 1945. In 1945, the Soviet Union declared war on Japan, and Manchukuo was subsequently invaded and abolished. The former puppet state was returned to China.

Mexico
Originally built as the Italian tanker Lucífero, the Potrero del Llano had been seized in port by the Mexican government in April 1941 and renamed in honor of a region in Veracruz. It was attacked and crippled by the German submarine U-564 on 13 May 1942. The attack killed 14 of 35 crewmen. On 20 May 1942, a second tanker, Faja de Oro (which was formerly the Italian Genoano, seized by Mexico one day after the Pearl Harbor attack) was attacked and sunk by the German U-160, killing 10 of 37 crewmen, and the Mexican government was prompted to declare war on the Axis powers on 22 May 1942. The Mexican Air Force's Escuadrón Aéreo de Pelea 201 (201st Fighter Squadron) served with the U.S. Fifth Air Force in the Philippines during the final year of the war.

Monaco
While Prince Louis II's sympathies were strongly pro-French, he tried to keep Monaco neutral during World War II, and he supported the Vichy France government of his old army colleague, Philippe Pétain. In 1943, the Italian army invaded and occupied Monaco, setting up a fascist government administration. Shortly thereafter, following Mussolini's collapse in Italy, the German army occupied Monaco and began the deportation of the Jewish population. Among them was René Blum, founder of the Ballet de l'Opera, who died in a Nazi extermination camp.

Mongolia
During the war, Outer Mongolia—officially the Mongolian People's Republic—was ruled by the communist government of Khorloogiin Choibalsan and was closely linked to the Soviet Union. Mongolia was considered a breakaway province of the Republic of China by most nations. Soviet–Mongolian relations were governed by a "gentlemen's agreement" from 27 November 1934, which was formalised in a mutual assistance pact on 12 March 1936. This treaty created a mutual defensive military alliance, and also pledged both parties to remove troops from the territory of the other when the need for military assistance had passed. On 13 August 1937, as part of their effort to support China in its war with Japan, the Soviets decided to station troops along Mongolia's southern and southeastern frontiers. To obtain the Mongolian government's consent, elaborate Japanese invasion plans were forged. On 24 August the Soviet deputy minister of defence, Pyotr Smirnov, and a small staff arrived in Mongolia to oversee the transfer of the Soviet 17th Army. The arrival of the Soviet army coincided, as planned, with a series of intensified terrors and purges (the "Great Terror"). In his address to the Third Session of the Supreme Soviet on 31 May 1939, Foreign Commissar Vyacheslav Molotov declared that "we shall defend the frontiers of the Mongolian People's Republic just as resolutely as our own border."

Mongolia reportedly signed an agreement with the Japanese puppet state of Manchukuo on 18 July 1940. In the Soviet–Japanese Neutrality Pact of 13 April 1941, the two powers recognised the neutrality of Mongolia and its place with the Soviet sphere of influence. Its geographical situation meant that it served as a buffer between Japanese forces and the Soviet Union. In addition to keeping around 10% of the population under arms, Mongolia provided supplies and raw materials to the Soviet military, and financed several units, for example the Revolutionary Mongolia tank brigade and Mongolian Arat Air Squadron and half million military trained horses. Also, more than 300 Mongolian volunteer military personnel fought in the Eastern European war theater.

Mongolian troops took part in the Battle of Khalkhin Gol in the summer of 1939 and in the Soviet invasion of Manchuria in August 1945, both times as small part in Soviet-led operations against Japanese forces and their Manchu and Inner Mongolian allies. During the 1945 campaign, the Mongolian troops were attached to the Soviet–Mongolian Cavalry Mechanized Group under Colonel General I. A. Pliev. The Mongolian units were the 5th, 6th, 7th and 8th Mongolian Cavalry Divisions, the 7th Motorized Armored Brigade, the Armored Car Brigade and the 3rd Artillery Regiment. On 10 August 1945, over twenty-four hours after the first Mongolian troops in the company of their Soviet allies had crossed the border into Japanese-occupied China, the Little Khural, the Mongolian parliament, issued a formal declaration of war against Japan.

For Mongolia, the most important result of World War II was the recognition of its independence by China, as provided by the Yalta agreement.

Morocco
Most of Morocco was a protectorate of France during World War II. When France was defeated, Morocco came under the control of the Vichy regime, and therefore was nominally on the side of the Axis powers, although an active resistance movement operated. In November 1942, it was invaded by the Allies as part of Operation Torch. From that point, Moroccan volunteers (the Goumier) fought on the side of the Allies.

A small area in northern Morocco, Spanish Morocco, was a Spanish protectorate and remained neutral throughout the war, as did the international city of Tangier.

Nauru
Nauru was administered by Australia under a League of Nations mandate. Nauru was shelled by a German surface raider in December 1940, aiming to incapacitate its phosphate mining operations (this action was probably the most distant military activity carried out by Germany during the entire war). Phosphates are important for making ammunition and fertilizers.

Nauru was occupied by Japan from 1942–45, and was the target of shelling by American battleships and cruisers, and aerial bombing by the Allies. For example, Nauru was bombarded by the USS North Carolina (BB-55), USS Washington (BB-56), USS South Dakota (BB-57), USS Indiana (BB-58), USS Massachusetts (BB-59), and the USS Alabama (BB-60), on 8 December 1943, and also bombed by U.S. Navy carrier airplanes on the same day. See the article on the USS Washington.

Nepal
Nepal declared war on Germany on 4 September 1939, and offered Gurkha troops to the United Kingdom.

Netherlands
Like the Belgians, the Netherlands declared neutrality in 1939. In May 1940, the Netherlands was invaded after fierce resistance against the Nazis. Rotterdam and Middelburg were heavily bombed. The Dutch joined the Allies and contributed their surviving naval and armed forces to the defense of East Asia, in particular the Netherlands East Indies. Until their liberation in 1945, the Dutch fought alongside the Allies around the globe, from the battles in the Pacific to the Battle of Britain. On the islands of Aruba and Curaçao (Netherlands West Indies) a large oil refinery was of major importance for the war effort in Europe, especially after D-day. As protection, a considerable U.S. military force was stationed on the island.

Newfoundland
During World War II the Dominion of Newfoundland was a part of the British Commonwealth. It joined the war on 4 September 1939, declaring war on Germany. Aware that a German invasion of Newfoundland could be used as a bridgehead for an attack on Canada, in 1940 Canadian Prime Minister William Mackenzie King and the Newfoundland Governor, Sir Humphrey T. Walwyn, entered into negotiations regarding the strengthening of defensive positions along the Newfoundland coast. Notwithstanding their separate political identities, the defenses of Newfoundland, and the Newfoundland Home Guard forces, were integrated with the Canadian military, and both governments agreed to the formation of a joint coastal defense organization. As part of the Anglo-American Destroyers for Bases Agreement, the United States was granted Air Force and U.S. Navy bases on Newfoundland's territory at Argentia, Stephenville, and St John's.

Newfoundlanders were encouraged to enlist in the large armed forces of the United Kingdom and of Canada. Over 3,200 Newfoundlanders enlisted in the Royal Navy. On 14 September 1939, The Royal Navy requested 625 experienced fishermen or seamen for special service in the Northern Patrol, guarding the Atlantic shipping lanes. Winston Churchill was particularly interested in these recruits, calling them "the hardiest and most skilful boatmen in rough seas who exist."

The Royal Artillery raised two regiments, the 57th Newfoundland Field Regiment, which fought in North Africa and Italy, and the 59th Newfoundland Heavy Artillery, which fought in Normandy and northwestern Europe. Another 700 Newfoundlanders served in the Royal Air Force, most notably with the 125th Newfoundland Squadron. In all, some 15,000 Newfoundlanders saw active service, and thousands more were engaged in the hazardous duty of the Merchant Navy. Some 900 Newfoundlanders (including at least 257 Merchant Mariners) lost their lives in the conflict, and over 100 Newfoundlanders were killed in the sinking of the SS Caribou by a German U-boat.

Newfoundland might have been the only location in North America to be subject to direct attack by German forces in World War II when German U-boats attacked four Allied ore carriers and the loading pier at Bell Island. The cargo ships S.S. Saganaga and S.S. Lord Strathcona were sunk by the U-513 on 5 September 1942, and the S.S. Rosecastle and P.L.M. 27 were sunk by the U-518 on 2 November 1942, with the loss of 69 lives. However, Allied ships (including American and Mexican ones) were sunk within sight of the North American shoreline (inside the territorial waters), and teams of German saboteurs landed via U-boats in New York State and in Florida. Also, German troops were landed on Greenland and Labrador, Newfoundland to establish weather stations, and they were prepared to shoot.

New Zealand
New Zealand declared war on 5 September 1939, backdating the date to the time of Britain's declaration.


 * "With gratitude for the past and confidence in the future, we range ourselves without fear beside Britain. Where she goes, we go; where she stands, we stand. We are only a small and young nation, but we march with a union of hearts and souls to a common destiny."

New Zealand sent one Army division that served in Greece, North Africa, and Italy, and it offered a fair number of pilots and aircrew to the Royal Air Force in England. Royal New Zealand Navy warships fought in the South Atlantic, including in the Battle of Rio de la Plata in 1939, before being called back to defend the homeland.

New Zealand fought in the Pacific War through warships of the Royal New Zealand Navy (RNZN), the Royal New Zealand Air Force (RNZAF), and independent army brigades, such as on Vella Lavella. While New Zealand's home islands were not attacked, the casualty rate suffered by the military was the worst per capita of all Commonwealth nations, except for Great Britain.

In the South West Pacific theater, the RNZAF participated in a unique force, AirSols, in the Solomon Islands, consisting of squadrons from the U.S. Marine Corps, U.S. Navy, USAAF, and RNZAF, with occasional help from the Royal Australian Air Force.

Nicaragua
During the war, Nicaragua was ruled by Anastasio Somoza García, who had assumed the presidency after a military coup in 1937. Somoza was an ally of the United States, and Nicaragua declared war on Japan immediately after the attack on Pearl Harbor. Three days later, on 11 December, Nicaragua declared war on Germany and Italy, and, on 19 December, on Bulgaria, Romania, and Hungary.

Northern Rhodesia
Northern Rhodesia (later Zambia) was a British colony. As such, it was covered by the British declaration of war. Northern Rhodesian units served in East Africa, Madagascar and Burma.

Norway
Norway was strategically important because it was a route for the transport of iron ore from Sweden to Germany, via Narvik. Winston Churchill had from the beginning of the war stated his wish for fighting Nazi Germany on Norwegian and Scandinavian soil, to prevent damages to central Europe as was seen in the previous war. The German Kriegsmarine had also promoted the advantages of naval bases in Norway. The integrity of her territory was further compromised when the German tanker Altmark was boarded, in Norwegian waters, from the British destroyer HMS Cossack in order to release British merchant seamen held captive (Altmark Incident).

Norway remained neutral until it was invaded by Germany on 9 April 1940, as part of Operation Weserübung. The Norwegian government fled the capital and after two months of fighting went to Britain and continued the fight in exile.

The Norwegian Shipping and Trade Mission (Nortraship) was established in London in April 1940 to administer the Norwegian merchant fleet outside German-controlled areas. Nortraship operated some 1,000 vessels and was the largest shipping company in the world. It is credited for giving a major contribution to the Allied war effort.

British politician, Philip Noel-Baker, Baron Noel-Baker commented after the war that "The first great defeat for Hitler, was the battle of Britain. It was a turning point in history. If we had not had the Norwegian fleet of tankers on our side, we should not have had the aviation spirit to put our Hawker Hurricanes and our Spitfires into the sky. Without the Norwegian merchant fleet, Britain and the allies would have lost the war."

After the occupation, the Germans began producing a critical material used in the manufacture of atomic bombs in Norway: heavy water. An Anglo-Norwegian operation to destroy the facility at Norsk Hydro Heavy Water Plant was aborted after the loss of British airborne engineers. A subsequent operation by Norwegian commandos in February 1943 successfully destroyed stores of heavy water and equipment. A raid of American heavy bombers in November persuaded the Germans that the area was unsafe, and they decided to move heavy water supplies to Germany. While en route, Norwegian agents planted explosives and sank a ferry carrying the heavy water and other machinery needed for bomb development.

The Allies maintained a deception of a planned invasion of Norway and commando raids on coastal installations supported this. As a result, additional German troops were held there and the German surface fleet were kept in Norwegian waters to repel any attempts. In 1944, Finnmark was liberated by the Soviet Union, and (together with the northern parts of Troms) totally destroyed by the retreating Nazis, while the German forces in the rest of Norway surrendered on 8 May 1945.

Norway declared war on Japan on 6 July 1945, with reciprocal effect dating back to 7 December 1941. The delay in the formal declaration against Japan had been caused by the need for the Norwegian Parliament to approve such an act in advance, and it had been impossible for the parliament to convene during the German occupation. Several hundred Norwegian sailors died when their ships were sunk by Japanese forces or during subsequent captivity. Around 300 Norwegian sailors were held as PoWs by the Japanese during World War II. After the war, Norway became one of the founding members of NATO.

Oman
The Sultan of Oman declared war on Germany on September 10, 1939.

Palestine
Palestine remained under the British Mandate system during the war. During the war, it acted as a location of hostilities, as a staging area for the British and a source of troops. In July 1940, Italy began bombing Tel Aviv, Haifa and other coastal cities.

Since Nazi Germany was seen as a greater threat, David Ben-Gurion ordered the Jews in Palestine to set aside their grievances against the British stemming for the 1939 White Paper restricting Jewish immigration to Palestine, stating "support the British as if there is no White Paper and oppose the White Paper as if there is no war". The Irgun also felt this way and many of its leaders were released from prison. The more radical branch of the Irgun disagreed and, on 17 July 1940, it split under the leadership of Avraham Stern and became known as "The National Military Organization in Israel" as opposed to Irgun's official name, "The National Military Organization in the Land of Israel". It would later changed its name to Lehi, referred to by the British as the "Stern Gang", as a completely separated militia.

During the Syria–Lebanon Campaign starting on 8 June 1941, many volunteers from Palestine participated in the fighting, including Palmach units that had been attached to allied troops. It was during this campaign that Moshe Dayan, attached to the Australian 7th Division, lost an eye, requiring him to wear what would become his trademark eye-patch.

In order to maintain the status quo ante bellum between the Jews and the Arabs, the British instated a policy of equal recruitment from both groups to the Palestine Regiment. However, due to the events of the 1936–1939 Arab revolt in Palestine and the alliance of exiled former Grand Mufti of Jerusalem Hajj Mohammad Amin al-Husayni with Adolf Hitler, only one Arab volunteered for every three Jewish volunteers. On August 6, 1942, the policy was relinquished and the regiment was formed, containing three Jewish battalions and one Arab. The regiment was assigned mostly to guard duty in Egypt and North Africa.

On 3 July 1944, Britain agreed to allow the Jews to fight against the Nazis directly and not just in a supportive role. Thus the three Jewish battalions of the Palestine Regiment together with the 200th Field Regiment were reorganized under the aegis of the Jewish Brigade, which would see action in Italy.

At the start of the war, approximately a thousand German nationals residing in Palestine known as Templers were deported by Britain to Australia, where they were held in internment camps until 1946–47. Although some had been registered members of the Nazi party and Nazi marches had taken place in their settlements, no evidence had been presented until 2007 that the majority supported Hitler. Although their property had been confiscated by the British authorities, the State of Israel chose to compensate them in 1962.

Panama
The small Panama Canal Zone was United States territory, and American forces from the U.S. Navy, U.S. Army, the USAAF (at Howard Air Force Base), and Colombian forces helped inside the Canal Zone, guarded the Panama Canal from both ends. This Canal provided the United States and its Allies with the ability to move warships and troops rapidly between the Atlantic Ocean and the Pacific Ocean. Since most of the American shipbuilding capability was on the East Coast and the Gulf of Mexico, the Canal was vital for moving new warships to the Pacific to fight the Imperial Japanese Navy .

Paraguay
Paraguay's authoritarian government under Higinio Moríñigo was sympathetic to the Axis powers early in the war; the country's large German community in particular were supporters of Nazism. Serious thought was given to joining the war on Germany's side, but United States President Franklin D. Roosevelt avoided this by providing aid and military hardware in 1942. Paraguay declared war on Germany on February 2, 1945, by which time the war was almost over.

Peru
Peru broke off relations with the Axis on 24 January 1942. Because of its ability to produce aviation fuel and its proximity to the Panama Canal, the oil refinery and port city of Talara, in northwest Peru, became an American air base. Although Peru did not declare war on Germany and Japan until 1945 (Peru declared a "state of belligerency"), the Peruvian Navy patrolled the Panama Canal area. As many as 2,000 Peruvian citizens of Japanese descent were detained and sent to the United States under American orders as part of the Japanese American internment policy.

Philippines
In 1941, the Philippine Commonwealth was a semi-independent commonwealth of the United States. The Philippine Army was commanded by American General Douglas MacArthur, and the Philippines was one of the first countries invaded by the Empire of Japan; combined Filipino and American forces maintained a stubborn resistance against the invasion. General MacArthur was ordered by the President to withdraw his headquarters to Australia, where he made his famous statement "I came out of Bataan, and I shall return". The Americans in the Philippines surrendered at Corregidor, on 6 May 1942.

Despite the official surrender, there was a significant local resistance movement to the Japanese Occupation. Elements of the Philippine Army continued their activity and were able to free all but twelve of the then-fifty Provinces of the Philippines, whilst other groups such as the Hukbalahap were also involved. While in exile, President Manuel L. Quezon continued to represent the Philippines until his death from tuberculosis in 1944. American forces under General MacArthur made their return in October 1944, beginning with amphibious landing on Leyte.

Poland
The Second World War started in September 1939, as Poland suffered an attack by Nazi Germany and later by the USSR. Many Polish troops and servicemen escaped the occupied country. They reorganized in France and took part in the Battle of France. Later Poles organized troops in the United Kingdom and were integrated into the forces of Britain with Polish pilots serving with distinction in the Battle of Britain. Poland was the only German-occupied country that never had no official collaboration with the Nazis. The Polish Resistance Movement was the largest anti-Nazi resistance in the whole Nazi-occupied Europe, and the only non-Communist resistance among the Slavic countries. It is remembered for its daring and brave methods of resisting occupation, often facing German forces in pitched battle. Polish armies also reformed in Soviet territory. The Polish-Jewish community was mostly exterminated in the Holocaust in Nazi-occupied Poland, while Poles themselves were considered to be a threat to the "German race", and were classificated as "subhumans". Millions of Poles were sent to concentration camps or were killed in other fashions in occupied Poland. German-occupied Poland was the only territory where any kind of help for Jews was punishable by death for the helper and his whole family. Even though, many Polish civilians risked their lives, and the lives of their families, to save the Jews from the Nazis. Moreover, Poles created "Żegota" - the only existing organization in occupied Europe, that was entirely focused on helping the Jews.

Portugal
For the duration of World War II, Portugal was under the control of the dictator António de Oliveira Salazar. Early in September 1939, Portugal proclaimed its neutrality to avoid a military operation in Portuguese territory by the Axis or Allies. This action was welcomed by Great Britain and reaffirmed historic Anglo-Portuguese treaties with England dating from 1373 (Anglo-Portuguese Alliance) and 1386 (Treaty of Windsor). Germany's invasion of France brought the Nazis to the Pyrenees, which allowed Hitler to bring unanticipated pressures on Portugal and Spain.

Following the Nazi invasion of Russia, which cut off their supply of tungsten metal from Asia, Germany initiated tactics to extract tungsten from Portugal. Initially, Germany artificially ran up prices in an attempt to get the people to bypass the Portuguese government and sell directly to German agents. Salazar attempted to limit this, and in October 1941, Germany sank a Portuguese merchant ship, the first neutral ship to be sunk in World War II. A German U-boat torpedoed a second Portuguese ship in December.

Despite efforts to resist, and because of the German threat to Portuguese merchant trade, in January 1942 Salazar signed an agreement to sell tungsten to Germany. In June 1943, Britain invoked the long-standing Anglo-Portuguese Alliance requesting the use of the Azores, to establish an air force and naval air base. Salazar complied at once. The Allies then promised all possible aid in the event of a German attack against Portugal. Additionally, the United States and Great Britain guaranteed the integrity of Portugal's territorial possessions. In 1944, Portugal declared a total embargo of tungsten shipments to Germany. Although the German Ambassador in Lisbon protested the Azores agreement, Germany never retaliated against Portugal.

Even while under intense German pressure, and with the presence of Nazi spies in Portugal, Lisbon became a safe-haven to a scattering of Jews from all over Europe. At the outbreak of World War II, Jewish refugees from Central Europe were granted resident status. After the German invasion of France, Portugal adopted a liberal visa policy, which allowed thousands of Jewish refugees to enter the country. As the war progressed, Portugal gave entry visas to people coming via rescue operations, on the condition that Portugal would only be used as a transit point. Portugal also joined other "neutral" countries in the efforts made to save Hungarian Jews. More than 100,000 Jews and other refugees were able to flee Nazi Germany into freedom via Lisbon. By the early 1940s, there were thousands of Jews arriving in Lisbon and leaving weeks later to other countries, such as in South America and Africa. Only a small minority stayed in Portugal.

Portuguese Macau
Although the Japanese military invaded and occupied the neighboring British colony of Hong Kong in 1941, they initially avoided direct interference in the affairs of Macau. Although it remained neutral territory, belonging to Portugal, Portuguese authorities lacked the ability to prevent Japanese activities in and around Macau. In 1943, Japan ordered the government of Macau to accept Japanese advisors. The limited Portuguese military forces at Macau were also disarmed, although Macau was never occupied.

Portuguese Timor
In early 1942, Portuguese authorities maintained their neutrality, in spite of warnings from the Australian and Dutch East Indies governments that Japan would invade. To protect their own positions in neighboring Dutch Timor, Australian and Dutch forces landed in Portuguese Timor and occupied the territory. There was no armed opposition from Portuguese forces or the civilian population. However, within a matter of weeks, Japanese forces landed but were unable to subdue substantial resistance, in the form of a guerrilla campaign launched by Allied commandos and continued by the local population. It is estimated that 40,000–70,000 Timorese civilians were killed by Japanese forces during 1942–45.

Romania
Romania had its first involvement in the war in providing transit rights for members of the Polish government, its treasury, and many Polish troops in 1939. During 1940, threatened with Soviet invasion, Romania ceded territory to the Soviet Union, Hungary, and Bulgaria, and following an internal political upheaval, Romania joined the Axis. Subsequently, the Romanian army participated with over 600,000 men in the German-led invasion of the Soviet Union, with its forces taking part in the capture of Odessa and Sevastopol and ultimately suffering irrecoverable losses at Stalingrad. Romania was also a major source of oil for Nazi Germany via the Ploiești oil fields.

With the entry of Soviet troops into Romania and a royal coup in August 1944, a pro-Allied government was installed, and after Germany and Hungary declared war on Romania, the country joined the Allies as a co-belligerent for the remainder of the war. The total number of troops deployed against the Axis was 567,000 men in 38 army divisions. The Romanian Army was involved in the siege of Budapest and reached as far as Czechoslovakia and Austria.

After the war, Romania forcefully became a people's republic as the country fell under the Soviet sphere of influence and joined the Warsaw Pact.

Samoa
Samoa declared war on Germany along with New Zealand, which administered all of Western Samoa under a League of Nations Mandate. Prior to World War I, Samoa had been a German colony and was occupied by New Zealand in 1914. Under the Treaty of Versailles, Germany relinquished its claims to the islands.

Samoa sent many troops to fight with the New Zealand armed forces in the war. After the sinking of a Samoan food ship by the Japanese flak gun ship Horisjimo in 1940, the Samoan government was forced to dispatch a light-gunned ship. The HMS Fa'i was in action and sank 7 ships, including the flak gun ship Horisjimo and a heavy gunner Koppiloskij. When the American armed forces entered Samoa, using it as a port, four midget submarines were spotted entering the capital Apia's port. The Samoan home guard reacted by firing a fair amount of rounds, resulting in the sinking of the Hirojimi and the Shijomiki.

San Marino
Ever since the times of Giuseppe Garibaldi, San Marino has maintained strong ties with the Italian state. Throughout the war, San Marino maintained its neutrality, although it did not remain unscathed from both sides. On 17–20 September 1944 retreating German troops of the 278th Infantry Division fought a battle within the country against units of the 4th Indian Division. By the 20th, the capital, San Marino, had been captured by the Indian troops who then advanced out of the country by the next day.

Saudi Arabia
Saudi Arabia severed diplomatic contacts with Germany on 11 September 1939, and with Japan in October 1941. Although officially neutral, the Saudis provided the Allies with large supplies of oil. Diplomatic relations with the United States were established in 1943. King Abdul Aziz Al-Saud was a personal friend of Franklin D. Roosevelt. The Americans were then allowed to build an air force base near Dhahran. On 28 February 1945, Saudi Arabia declared war on Germany and Japan, but no military actions resulted from the declaration.

Singapore
Singapore was part of the Straits Settlements, a British Crown colony, and is in a strategic location for shipping routes connecting Asia to Europe. For these reasons, Japan invaded Singapore in the Battle of Singapore from 7 February to 14 February 1942. The city was renamed Syonan and kept under Japanese occupation until the end of the war in September 1945.

Slovakia
The newly separated Slovak Republic, a Nazi-dependent puppet regime, led by Jozef Tiso was ultimately inserted in Slovakia. Part of southern Slovakia as well as the complete Ruthenia (the former most eastern part of Czechoslovakia) was annexed by Hungary. Zaolzie was annexed by Poland, only to be snatched from them by the Germans 11 months later. In 1945 the victorious Soviet Union returned Zaolzie to Czechoslovakia. From 1940, a government-in-exile in London under former Czechoslovak President Edvard Beneš was recognized as an Allied power. The Slovak National Uprising, commenced in August 1944, was suppressed by German forces at the end of October; partisans, however, continued fighting in the mountains until the war's end. In April 1945, the Red Army defeated the Germans and ousted Tiso's government, annexing Carpathia Ruthenia to the USSR.

South Africa
As a member of the British Commonwealth, the Union of South Africa declared war on Germany shortly after the United Kingdom, on 6 September 1939. Three South African infantry divisions and one armoured division fought under Allied commands in Europe and elsewhere, most notably in the North African campaign and the Italian campaign. Most of the South African 2nd Division was taken prisoner with the fall of Tobruk on 21 June 1942. Under the Joint Air Training Scheme, part of the British Commonwealth Air Training Plan, South Africa trained 33,347 aircrews for the British Royal Air Force, South African Air Force and other Allied air forces. Only Canada trained more.

Southern Rhodesia
Southern Rhodesia (modern-day Zimbabwe) had been a self-governing British colony since 1923. It was covered by the British declaration of war, but its colonial government issued a symbolic declaration of war anyway. Southern Rhodesia's white troops did not serve in a composite unit (unlike their Australian, Canadian, or South African counterparts) because they constituted a significant part of the settler population; it was feared that the colony's future might be placed in jeopardy if an all-Southern Rhodesian unit went into the field and suffered heavy casualties. Southern Rhodesians served in East Africa, Europe, North Africa, the Middle East and the Burma Campaign. A significant number of Southern Rhodesian troops, especially in the Rhodesian African Rifles, were black or mixed race. Their service has never been recognised by the ZANU–PF government in Harare. Ian Smith, the future Prime Minister, like many of his white contemporaries, served under British command as a fighter pilot in the Royal Air Force.

Soviet Union
The Soviet Union's participation in World War II began with the Battle of Khalkhin Gol, with Japan in Mongolia in 1939. Later that year, protected with the Molotov-Ribbentrop Pact, it invaded eastern Poland about three weeks after the Germans invaded the west of the country. During the next eleven months the Soviets occupied and annexed the Baltic states (Estonia, Latvia, and Lithuania). The Soviet Union supported Germany in the war effort against Western Europe through the 1939 German–Soviet Commercial Agreement and larger 1940 German–Soviet Commercial Agreement with supplies of raw materials, significantly weakening the British naval blockade.

Following Finland's refusal of Soviet demands for military bases and a territorial swap, the Soviet Union invaded on 30 November 1939, in the Winter War. The Soviet Union also annexed Bessarabia (a Romanian province since 1918), leading Romania to ally with Germany. Germany launched a surprise attack on the Soviet Union in 1941. Thereafter, most of the German forces were concentrated on the Eastern Front. The USSR played a crucial role in the defeat of Nazi Germany.

The Soviet Red Army mounted a successful counter-offensive during the winter, and gained the initiative with a series of major victories in 1943, culminating in the ultimate advance of Soviet forces into Eastern Europe and Germany in 1945, concluded with the Battle of Berlin. The Soviet Union suffered greater losses, both among civilians and military forces, than any of the other participants in the war. Following the end of the war in Europe and the American atomic bombing of Hiroshima, the USSR declared war on Japan in 1945. The Soviet Union became one of the main victors and gained one of the permanent seats in the United Nations Security Council. After the war, the Soviet sphere of influence was widened to cover most of Eastern Europe, formalized in the Warsaw Pact, to counter the western Allies and NATO. The Soviet Union came to be considered one of the two superpowers of the Cold War. The Soviet Union held the largest manufacture of tanks in the war, with the T-34.

Spain
The Franco government of Spain had risen to power as a result to a significant degree of Italian and German intervention and support. Spain, which was suffering the aftermath of the recently finished Spanish Civil War, did not have the resources to join the war on its own, and Franco and Hitler did not achieve an agreement about the terms of the Spanish participation. Despite its non-belligerency, Spain sent volunteers to fight alongside Germans against the Soviet Union in the form of the Blue Division. As the Allies emerged as possible victors, the regime became more neutral, at least in theory, finally declaring its neutrality in July 1943 although the complete removal of Spanish troops from Eastern Front was not completed until March 1944. Although it sought to avoid entering the war, Spain did make plans for defence of the country. Initially, the mass of the Spanish army was stationed in southern Spain in case of an Allied attack from Gibraltar during 1940 and 1941. However, Franco ordered the divisions to gradually redeploy in the mountains along the French border in case of a possible German invasion of Spain as Axis interest in Gibraltar grew. By the time it became clear that the Allies were gaining the upper hand in the conflict, Franco had amassed all his troops on the French border and received personal assurances from the leaders of Allied countries that they did not wish to invade Spain.

Sweden
Sweden maintained neutrality throughout the war, though some Swedish volunteers participated in the Winter War and in the Continuation War against the Soviet Union.

After Denmark and Norway were invaded on 9 April 1940, Sweden and the other remaining Baltic Sea countries became enclosed by Nazi Germany and the Soviet Union, then on friendly terms with each other as formalized in the Molotov–Ribbentrop Pact. The lengthy fighting in Norway resulted in intensified German demands for indirect support from Sweden, demands that Swedish diplomats were able to fend off by reminding the Germans of the Swedes' feeling of closeness to their Norwegian brethren. With the conclusion of hostilities in Norway this argument became untenable, forcing the Cabinet to give in to German pressure and allow continuous (unarmed) troop transports, via Swedish railroads, between Germany and Norway. At most there were more than 350,000 German soldiers in Norway. A considerable force was fighting from Finnmark (Kirkenes port etc.) against the Russians near Murmansk.

Switzerland
Switzerland intended to be a neutral power during the war, but Axis threats and military mobilizations towards its borders prompted the Swiss military to prepare for war. Following the German invasion of Poland on 1 September 1939, this country was completely mobilized within three days. Though a Nazi invasion of Switzerland, codenamed Operation Tannenbaum was planned for 1940, the event never ultimately occurred because Hitler decided such a conflict would be a waste of resources at a time when he preferred to concentrate on the invasion of Britain. Unlike the Netherlands, Belgium, and other western European nations that had easily fallen under Nazi invasion, Switzerland had a strong military and a mountainous geographic terrain that would have likely made an invasion long and difficult.

Despite its neutrality, Switzerland was not free of hostilities. Early in the war, several German aircraft were shot down by Swiss fighters for violating Swiss air space. Hundreds of aircraft on both sides, which landed in Switzerland, such as with battle damage, were interned at Swiss airports and their crews held until the end of the war. Allied airmen were interned, in some cases, contrary to Swiss law, and some were reportedly subjected to abuse in internment camps. Several Swiss cities were accidentally bombed by both sides. In time, Switzerland was unofficially proclaimed its own side in the war because of its defensive and hostile nature towards both sides. Although the Swiss government was anti-Nazi, Swiss troops did not directly intervene in the European conflict. It became embroiled in post-war controversies regarding the appropriation of assets belonging to Holocaust victims and Nazi officials' use of Swiss banks to keep their money safe.

Syria
Syria was under French control throughout the war. Following the French surrender in 1940, this was the 'Vichy' government, a puppet of the Nazi regime. Churchill had fears about the use of Syria to threaten Britain's Iraqi oil supplies. These appeared to be substantiated when Luftwaffe supply flights to the new pro-German Iraqi regime (under Rashid Ali) refuelled in Damascus.

In June 1941, British and Free French forces invaded Syria, and after giving effective opposition, the Vichy forces surrendered in July 1941. British occupation lasted until the end of the war. The province of İskenderun was given to Turkey to be kept neutral in the war.

Thailand
Thailand was nominally an ally of Japan at the beginning of the war. The country was ruled at first by Field Marshal Plaek Phibunsongkhram, a military dictator with nationalist leanings, under the Thai King. Thailand remained uninvolved when war broke out in Europe, but it took the opportunity of France's defeat to settle historical claims to parts of French Indochina. The conflict between Thailand and the Vichy regime is known as the French–Thai War. In 1941, the Japanese entered Thailand, and they used it as a stepping-stone to invade Burma and easternmost India. Phibun, while reluctant, believed that Japan's superior military power gave Thailand no choice but to order an armistice, and he allowed the Japanese military to pass through.

The Premier became more enthusiastic about co-operation with Japan when the Japanese performed well in Malaya, and on 21 December, a formal "alliance" was concluded. At noon on 25 January 1942, Thailand declared war on the United States and Great Britain. Some Thais supported the alliance, arguing that it was in the national interest, or arguing that it was better sense to ally oneself with a victorious power. Others formed the Free Thai Movement to resist. Eventually, when the war turned against the Japanese, Phibun was forced to resign, and a Free Thai-controlled government was formed. On 16 August 1945, Thailand rescinded its declarations of war.

Tonga
The Queen of Tonga, Salote Tupou III, put her island country's resources at the disposal of Britain and was a loyal supporter of the Allied cause throughout the war.

Transjordan
The Emirate of Transjordan was a British mandate territory, and the Transjordanian forces were under British command during the war.

Turkey
Turkey was neutral until several months before the end of the war, at which point it joined the Allies. Prior to the outbreak of war, Turkey signed a Mutual Aid Pact with France and Britain in 1939. After the German invasion of France, however, Turkey remained neutral, relying on a clause excusing them if military action might bring conflict with the USSR, which, after the division of Poland, Turkey feared. Then, in June, 1941, after neighboring Bulgaria joined the Axis and allowed Germany to move troops through to invade Yugoslavia and Greece, Turkey signed a non-aggression pact with Germany. Turkey was an important producer of chromite, a key ingredient in the manufacture of stainless steel and refractory brick to which the Germans had limited access. Sale of chromite to Germany or to the Allies (who had access to other sources and mainly bought in order to preclude sale to Germany) was the key issue in Turkey's negotiations with both sides. Turkey halted its sales to Germany in April, 1944 and broke off relations in August. In February, 1945, after the Allies made its invitation to the inaugural meeting of the United Nations (along with the invitations of several other nations) conditional on full belligerency, Turkey declared war on the Axis powers, but no Turkish troops ever saw combat.

United Kingdom
The United Kingdom was one of the original Allies, entering the war in 1939 to honour its guarantees to Poland. After the fall of France, the United Kingdom was the only Allied nation left in Europe until the invasion of Greece. It remained the only one of the Big Three in the war until 1941 when the Soviet Union was invaded. The United Kingdom was heavily engaged in the Western European, Atlantic, Mediterranean, African and South East Asian theatres, and was considered one of the Big Three during Allied conferences in the second half of the war. The United Kingdom maintained close ties with the nations of the British Empire, and the forces of those countries were often incorporated into British military operations.

Northern Ireland
As a part of the United Kingdom, Northern Ireland participated fully as a belligerent. The particular contributions were manpower (see above), food, armaments, and its unique geographical location. Despite urgings from the Stormont government, mandatory conscription was never implemented in Northern Ireland due to Irish nationalist opposition, which echoed nationalist agitation against conscription during World War I.

As part of fears over the invasion of Northern Ireland via Plan Kathleen, or the invasion of Ireland via Plan Green, the British and Irish conducted joint planning to repel a German invasion under the guise of Plan W. Joint training between Irish Defence Force personnel and British special operations personnel also took place in County Down.

United States of America
The United States was neutral early in the fight, although it steadily grew ties with the Allies and began providing increased levels of assistance to them. The United States joined the Allies in December 1941 after the Japanese attack on Pearl Harbor, when war was declared by the Empire of Japan on 7 December 1941.

Germany and Italy declared war on the United States three days later. The United States subscribed to the Allied plan of making German defeat the priority, where it operated in coordination with the United Kingdom in most major operations. However, it also maintained a strong effort against Japan, being the primary Allied power in the Pacific Theatre. The U.S. played an important role in providing valuable industrial production to support the Allied war effort. After the war, the United States retained military commitments to European security while providing economic investment to rebuild nations suffering devastation during the war. Politically, the U.S. became a founding member of NATO, and hosts the United Nations in which it gained one of the permanent chairs on the Security Council.

Uruguay
Uruguay was neutral for most of World War II, although later joined the Allies. It declared its neutrality on September 4, 1939, although President Alfredo Baldomir was poorly disposed towards the Axis powers. Uruguay's neutrality included a 500 km exclusion zone extending from its coast, established as part of the Declaration of Panama.

Neither side of the conflict acknowledged the exclusion zones established by the declaration, and in December, British warships and the German ship Admiral Graf Spee fought a battle not far off Uruguay's coast. This prompted a joint protest from several Latin American nations to both sides. (Admiral Graf Spee took refuge in Uruguay's capital, Montevideo, claiming sanctuary in a neutral port, but was later ordered out.) In early 1942, President Baldomir broke off diplomatic relations with the Axis Powers. On 15 February 1945, near the end of the war, Uruguay dropped its policy of neutrality and joined the Allies. Uruguayan pilots, along with volunteers from other countries, joined the Free French Forces.

Vatican City
Vatican City, at 0.44 km2 the smallest autonomous country in the world, was neutral and remained unoccupied throughout the war. The Italians, and later, the Germans, blockaded the state and occasionally harassed the citizens within. The Vatican was a refuge for a small number of Jews. It was a site of political debate and communications between the belligerent sides. During the bombings of Rome, both sides were instructed by their commanders not to bomb the state. However, whether accidentally or not, a single bomber dropped five bombs on the Vatican on 5 November 1943, destroying a mosaic and blasting out the windows of the cupola of St. Peter's Basilica.

Venezuela
After the attack on Pearl Harbor, Venezuela severed diplomatic relations with Italy, Germany, and Japan, and after implementing (with help from the United States) defenses on the oil wells (there was information that Germany had plans to invade the South American continent from Venezuela and seize its oil production) produced vast oil supplies for the Allies. It maintained a relative neutrality until the last years of war, when it finally declared war on Germany and the rest of the Axis countries.

Yemen
The Mutawakkilite Kingdom of Yemen, which occupied the northern portion of modern Yemen, followed an isolationist foreign policy under King Yahya Muhammad Hamid ed-Din. It formed an alliance with Italy in 1936, and yet it remained neutral for the duration of the war. The southern portion of modern Yemen, known as the Aden Protectorate, was under British control.

Yugoslavia
The Axis Powers occupied Yugoslavia in 1941 and created several puppet states. The Independent State of Croatia was a German and Italian puppet state. The Nedić's Serbia was a German client state. The Kingdom of Montenegro was an Italian puppet state from 1941 to 1943 and a German puppet state from 1943 to 1944. Other parts of Yugoslavia were occupied directly by Germany, Italy, Bulgaria and Hungary. Yugoslavs opposing the Nazis soon started to organize resistance movements, the Partisans, led by Josip Broz Tito and Communist Party of Yugoslavia, and the monarchist Chetniks. The two movements had conflicting goals, and the Chetniks started to collaborate with the Axis powers to fight against the Partisans.

Communist Anti-Fascist Council of National Liberation of Yugoslavia was convened on in Bihać in 1942 and in Jajce in 1943, and the latter assembly established the basis for the post-war organization of the country as a federal republic. Near the end of the war, Western governments had attempted to reconcile the partisans and the government-in-exile loyal to the king, which led to the Tito-Šubašić Agreement in June 1944, but, effectively, Communist Party gained the exclusive power in post-war state.

After heavy bloodshed in the war, which was at the same time liberation, ethnic and civil war, Yugoslavia was reestablished in 1945, expanding territories on areas previously ruled by Kingdom of Italy (Istria and parts of Dalmatia). After the war, General Mihailović and many other royalists were rounded-up and executed by the Partisans for collaboration with the Nazis. Mihailović was posthumously awarded the Legion of Merit by President Harry S. Truman for his role in Operation Halyard.