Portugal during World War I

Monument to the Portuguese soldiers who died in World War I in Coimbra, Portugal

Despite having an old alliance with Britain dating back to the Treaty of Windsor in 1386 (the oldest alliance in the world which is still in force), Portugal did not initially form part of the system of alliances involved in World War I and thus initially kept its neutrality. However, tensions between Germany and Portugal arose due to German U-boat warfare which sought to blockade the United Kingdom — at the time the most important market for Portuguese products. Clashes also occurred with German troops in the south of Portuguese Angola in 1914 and 1915 (see German campaign in Angola).

Initially, both the Portuguese and the German Governments officially stuck to neutrality. Unofficially, there were many hostile engagements between the countries. Portugal wanted to comply with British requests and also protect its colonies in Africa, and ultimately tensions resulted in war between Portugal and Germany being declared, first by the latter.

Approximately 7,000 Portuguese troops died during the course of World War I, including Africans serving in its armed forces. Civilian deaths exceeded the prewar level by 220,000, 82,000 caused by food shortages and 138,000 by the Spanish flu.

1914

Portuguese troops embarking to Angola.

• July German and British Empires secretly negotiate about a possible dismemberment of Portuguese Angola; in such a case most of the land would fall into the hands of Germans. Angola-Bund founded in 1912 was the German organization promoting the takeover.
• August to September Skirmishes occurred between German and Portuguese colonial troops in Africa and the Germans instigated tribal revolts.
• September Portuguese government sent reinforcements to the southern border of Angola. After the war broke out the border between German South West Africa and Angola remained open. The Germans hoped to supply food and possibly even arms through it. However the Portuguese colonial government was hostile and tried to stop all the trade. A few German nationals in Angola were interned.
• October 1600 troops arrive in Portuguese Angola and 1527 troops arrive in Mozambique from Portugal, transported by British ships.

1915

• November 1543 troops arrive in Portuguese Mozambique, commanded by Moura Mendes. This 2ª force was to recapture the Kionga Triangle from the Germans.

1916–1918, Portugal in the war

When Portugal complied with the British request to confiscate the German ships interned in Portuguese ports, Germany reacted by declaring war on Portugal, thus forcing the Portuguese officially into the war.

1916

• February 23 Following a British request, Portugal interned 36 German and Austro-Hungarian ships in Lisbon.
• March 9 Germany declared war on Portugal followed by Portugal declaring war on Germany and starts to organise Portuguese troops to go to the Western front.
• June 9 Afonso Costa (Finance Minister) and Augusto Soares participated in an Allied Economic Conference where the Allies decided that as condition for peace, Germany would have to return the territories of Alsace-Lorraine to France (occupied since 1871) and Kionga in Portuguese Mozambique to Portugal (occupied since 1894).
• July 15 The British Government formally invited Portugal to take an active part in the military actions of the Allies.
• July 22 The Portuguese Expeditionary Corps (Corpo Expedicionário Português, CEP), with 30,000 soldiers, was established in Tancos, Portugal, under the command of General Norton de Matos.
• August 7 The Portuguese Parliament accepted the participation of Portugal in the war, following the invitation of the British Government. The Portuguese war effort reached 55,000 infantry soldiers, plus 1,000 artillerymen, to be sent to France—4,000 soldiers per month—to man 12 km of battlefront. In fact, only the first two divisions reached France, as the shipping of American troops drastically reduced the Allies' transportation capacity. At the same time, Portugal fielded forces in its African colonies, in Mozambique, to defend the colony from German colonial forces, and in the south of Angola, against native unrest instigated by the Germans.
• December 3 The German U-boat, SM U-38, captained by Max Valentiner went into Funchal harbour on Madeira and torpedoed and sank 3 ships, CS Dacia (1,856 tons), Kanguroo (2,493 tons) and Surprise (680 tons). The commander of the French Gunboat Surprise and 34 of her crew (7 Portuguese) died in the attack. The Dacia, a British cable laying vessel, had previously undertaken war work off the coast of Casablanca and Dakar, was in the process of diverting the German South American cable into Brest, France. Following the attack on the ships, the Germans proceeded to bombard Funchal for 2 h from a range of about 2 mi. Batteries on Madeira returned fire and eventually forced the Germans to withdraw.
• December 26 The French Government asked Portugal to send artillery crews to France to operate 20 to 30 heavy artillery batteries.

1917

Portuguese troops disembarking at Brest.

• Small amount of Portuguese troops sent to the New Forest, England to help in the timber shortage, working with the Canadian Forestry Corps, today the area is known as the Portuguese Fireplace.

• January 3 Convention with Great Britain to regulate Portuguese participation in the Western Front. Portuguese troops of the CEP would be integrated in the BEF (British Expeditionary Force).
• January 7 The Independent Heavy Artillery Corps (Corpo de Artilharia Pesada Independente, CAPI) was created to respond to the French request for artillery crews. Under a Portuguese Superior Command, this unit would operate 25 heavy artillery batteries.
• February 2 The first Portuguese troops arrived at the port of Brest, in Brittany, France.
• February 23 The second contingent of the CEP left for France.
• April 4 The Portuguese troops arrived at the front. First Portuguese casualty: Private António Gonçalves Curado (killed in action).
• May 30 The First Infantry Brigade of the CEP First Division occupied a sector in the battle front.
• June 4 German attack on the sector defended by the First Brigade.
• June 16 Second Infantry Brigade occupied another sector on the battle front.
• July 10 CEP First Division assumed responsibility of its part of the Portuguese sector on the battle front. It was subordinated to the XI Corps of the British Army, under the command of General Richard Haking. CEP Third Infantry Brigade occupied a sector on the battle front.
• September 23 The Fourth Brigade, known as the Brigade of Minho (Brigada do Minho), part of the Second Division, reached the front.
• October 17 The first Portuguese CAPI artillery soldiers, representing Portugal's direct support to the French war effort, arrived in France. They were designated by the French as Corps d'artillerie lourde portugais (CALP).
• November 5 Portuguese command assumed the responsibility for its sector in the front. Until this date, it had been under the command of General Henry Horne's British First Army.
• Late 1917 In Portuguese Mozambique, German officer Paul von Lettow-Vorbeck, after a series of long running battles with numerically superior British forces, entered the colony from nearby German East Africa.
• December 12 2 German U-boats, SM U-156 and SM U-157 (captaining by Max Valentiner) again bombarded Funchal, Madeira. This time the attack lasted around 30 min. Forty, 4.7 inch and 5.9 inch shells were fired. There were 3 fatalities and 17 wounded, In addition, a number of houses and Santa Clara church were hit.
• December 17The German U-boat SM U-156 Stops and scuttles the Portuguese ship Açoriano (a Wooden three-masted schooner) SE of the Azores
• December 26 The German U-boat SM U-157 (captaining by Max Valentiner) sinks the Portuguese ship Lidia in the Azores.

1918

Portuguese troops loading the Stokes Mortar

• February 17 The German U-boat SM U-157 (captaining by Max Valentiner) sinks the Portuguese ship Estrella de Bissao off the coast of South Africa.
• March 16 The Portuguese artillery batteries enter in action.
• March 27 A German offensive restrains the Portuguese soldiers from being released. As a third Portuguese Division was never sent to France, the Portuguese Army did not receive reinforcements at all. Portuguese soldiers had to serve in the battle front for long periods and were thus amongst the most exhausted men in the front.
• April 6 The condition of the Portuguese soldiers become so difficult that, finally, the British decided to release the Portuguese. The CEP was supposed to be reorganized, the First Division going to the rear as a reserve force and the Second Division becoming part of the Eleventh Corps of the British Army, under General Haking's command. Haking visits the Portuguese troops and decides to send the Second Division to the rear from April 9, which would never happen. The Germans attacked the British lines, forcing them to retreat about 60 km. Instead of being released, the Portuguese troops had to fight off the German offensive on its sector.

Portuguese prisoners-of-war in 1918.

• April 9 The Battle of La Lys, as it became known in Portugal, or Operation Georgette, or Battle of Estaires to the British, started with a heavy artillery barrage from the Germans, followed by a German offensive with intensive use of lethal gas. The German Sixth Army deployed eight divisions (about 100,000 men), supported by intensive artillery fire. Against this force, the Portuguese had 20,000 soldiers and 88 guns. As a result, the Second Division was annihilated during the battle. The Portuguese CEP lost 327 officers and 7,098 soldiers, about 35% of its effective fighting capacity. The survivors were sent to the rear, some of the units being integrated in the British Army later on. During this battle, one of the most courageous acts in Portuguese history was perpetrated, as private Aníbal Milhais (also known as "Soldado Milhões" ["A Soldier as good as a million others" in his commanding officer's words]) defended all alone the retreating allied forces with nothing but his machine gun, allowing them to fall back and regroup. Once he ran out of bullets, he escaped the battlefield, after defeating two German regiments and forcing the remaining German forces to go around him, finding impossible to defeat what they believed to be an heavily armed post, yet, he got lost along the way, having to eat nothing but sweet-almonds his family had sent him from Portugal for three days. Lost and exhausted, he was able to rescue a Scottish major from drowning in a swamp. This major led him to the Allied camp and told everyone Milhais' deeds.
• July General Tomás António Garcia Rosado is appointed as the new Commanding Chief of the remaining CEP.
• July German forces under von Lettow-Vorbeck captured Namakura/Nhamacurra in Portuguese East Africa and seized important arms and supplies for his force after similar smaller successes against Portuguese outposts had already helped reprovision his force.
• July 4 CEP First Division was subordinated to the British Fifth Army, commanded by General William Birdwood.
• August 25 General Garcia Rosado assumes command of the CEP in France. The German U-boat SM U-157 sinks the Portuguese ship Gloria, 30 miles from Porto Santo, Madeira Islands.
• September 22 The German U-boat SM U-157 sinks the Portuguese ship Gaia, near the Azores.
• October 14 In the Action of 14 October 1918 the Portuguese patrol boat NRP Augusto Castilho (commanded by Carvalho Araújo) is sunk by the German U-boat U-139 (commanded by Lothar von Arnauld de la Perière) after several hours of fighting.
• November 11 Germany accepts the armistice proposed by the Allies. The war ends.

Portugal had 8,145 dead, 13,751 wounded, and 12,318 prisoners or missing. At sea 96 Portuguese ships were sunk (100,193 tons) and 5 Portuguese ships were damaged (7,485 tons) by German submarines.

After the Armistice

1919

• January 18 The Portuguese delegation at the Peace Conference in Versailles, France, was led by Prof. Egas Moniz. In the Peace Treaty, Germany had to cede the port of Kionga, hitherto associated with German East Africa (the mainland of modern Tanzania), to Portugal.

1921

• November 19 Charles I the last Emperor of the Austro-Hungarian Empire went into exile on the Portuguese island of Madeira, where he would remain until his death on April 1, 1922. Charles I had tried in 1917 to enter secretly into peace negotiations with France. Although his foreign minister, Ottokar Czernin, was interested in negotiating only a general peace that would include Germany as well, Charles himself, in negotiations with the French with his brother-in-law, Prince Sixtus of Bourbon-Parma, an officer in the Belgian army, as an intermediary, went much further in suggesting his willingness to make a separate peace. When news of the overture leaked in April 1918, Charles denied involvement until the French Prime Minister Georges Clemenceau published letters signed by him. This led to Czernin's resignation, forcing Austria-Hungary into an even more dependent position with respect to its seemingly-wronged German ally. Determined to prevent a restoration attempt, the Council of Allied Powers had agreed on Madeira because it was isolated in the Atlantic and easily guarded.