III Corps (United States)

III Corps is a corps of the United States Army headquartered at Fort Hood, Texas. It is a major formation of the United States Army Forces Command.

Activated in World War I in France, III Corps oversaw US Army divisions as they repelled several major German offensives and led them into Germany. The corps was deactivated following the end of the war.

Reactivated in the interwar years, III Corps trained US Army formations for combat before and during World War II, before itself being deployed to the European Theater where it participated in several key engagements, including the Battle of the Bulge where it is known as the force that relieved the surrounded 101st Airborne Division.

For the next 50 years, the division would act as a key training element for the US Army as it sent troops overseas in support of the Cold War, the Korean War, and the Vietnam War. The corps would see no combat deployments, however, until Operation Iraqi Freedom in 2004. It has since seen multiple deployments to Iraq.

World War I
III Corps was first organized on 16 May 1918 in France. It was designed as three of the four newly activated corps of the American Expeditionary Force, which at that time number over 1,000,000 men in 23 divisions. The corps took command of US forces training with the French Seventh Army at the same time that IV Corps took command of US forces training with the French Eighth Army.

Aisne-Marne campaign
In July, the corps was rushed to the Villers-Cotterêts area in preparation for the Third Battle of the Aisne, the first major Allied counteroffensive of the year. There, it was put under the French Tenth Army and given administrative command of the 1st Division and the 2nd Division which were previously under command of the French XX Corps. However, the command group arrived in the area too late to exercise tactical command, and it was instead attached to the French XX Corps. On 18 July, the attack was launched, with the force spearheading the French Tenth Army's assault on the high ground south of Soissons. During this attack, the Corps also cut rail lines supplying the German Army.

The first day of the attack was a success, but on the second day, the Germans were reinforced with heavier weapons and were able to blunt the attack, inflicting high casualties. The force was successful despite heavy casualties, and German forces were forced to retreat. On 1 August, the corps arrived in the Vesle area near the Marne River, where it assumed command of the 3rd Division, 28th Division, and 32nd Division from the French XXXVIII Corps, placing side-by side with the U.S. I Corps for a few days. Troops continued to advance until September when they withdrew to form the new First United States Army.

Meuse-Argonne campaign
First Army formed up in preparation to advance in the Meuse-Argonne campaign. It consisted of over 600,000 men in I Corps, III Corps, and V Corps. III Corps took the Army's east flank, protecting it as the Army advanced to Montfaucon, then Cunel and Romagne. The offensive was slow and hampered by inexperience of many of the divisions under the Army's command, though III Corps was effective in protecting its sector. They advanced through September and October, taking a few weeks for rest after the formation of Second United States Army. On 1 November, the First Army went on a general offensive, pushing north to the Meuse River and the Barricourt Ridge. It was successful, pushing German forces back and advancing to the river until the end of the war. Around that time, the division received its shoulder sleeve insignia, approving it by telegram, though the insignia would not be officially authorized until 1922.

The corps was demobilized in Neuwied, Germany at the close of hostilities. Following the end of World War I, III Corps remained in Europe for several months before it returned to the United States. It was demobilized at Camp Sherman, Ohio.

Interwar Period
On 15 August 1927 the XXII Corps was activated in the United States. On 13 October of that year XXII Corps was redesignated as III Corps. It was formally activated on 18 December 1927. Throughout much of the next decade, the corps was directed primarily with training and equipping smaller units, as the US military began slowly building in strength in response to international conflicts. In 1940, III Corps was tasked specifically with training newly formed US Army combat divisions in preparation for deployment. It was moved to Camp Hood, Texas for this mission.

World War II
Following the Japanese attack on Pearl Harbor signaling the entrance of the US into World War II, III Corps remained in the United States, where it was assigned to organize defenses of the West Coast, specifically California, from the threat of attack from Japan. During this time III Corps operated at Monterey, California.

The corps was moved to Fort McPherson, Georgia in early 1942 for training. After a short period, the corps returned to Monterey and on 19 August 1942, it was designated a separate corps, capable of deployment. During the next two years, III Corps would train thousands of troops for combat, including 33 division-sized units, and participate in four corps-level maneuvers, including the Louisiana Maneuvers.

Europe
On 23 August 1944, the corps headquarters departed California for Camp Myles Standish in Massachusetts. It deployed for the European Theater of Operations on 5 September 1944. Upon arrival at Cherbourg, France, the corps was assigned to the Ninth Army, Twelfth United States Army Group, and given the code name "CENTURY" which it retained throughout the war. The corps headquarters was established at Carteret, in Normandy, and for six weeks, the corps received and processed all the troops of the 12th Army Group arriving over the Normandy beaches during that period. The corps also participated in the "Red Ball Express" by organizing 45 provisional truck companies to carry fuel and ammunition for the units on the front lines.

The corps was assigned to the Third United States Army on 10 October 1944, and moved to Etain, near Verdun, and into combat. The corps' first fighting was for the Metz region, as it was moved to attack Fort Jeanne d'Arc, one of the last forts holding out in the region. That fort fell on 13 December 1944.

Later that month on 16 December came the last German counteroffensive in the Battle of the Bulge, as over 250,000 German troops, supported by over 1,000 tanks and assault guns assaulted the lines of VIII Corps, some 40 miles to the north of III Corps. The next day, Third Army commander General George Patton warned III Corps that it would likely be ordered to assist. At that time the corps consisted of the 26th Infantry Division, 80th Infantry Division and the 4th Armored Division. III Corps was moved north to assist in the relief of Bastogne, with the attack commencing at 0400 on 22 December. The corps advanced north, catching the German forces by surprise on their south flank, cutting them off. The 4th Armored Division was eventually able to reach Bastogne, where the 101st Airborne Division had been surrounded by German forces, and relieve it. During the first 10 days of this action, III Corps liberated more than 100 towns, including Bastogne. This operation was key in halting the German offensive and the eventual drive to the Rhine River.

During the first four months of 1945, III Corps moved quickly to the offensive. On 25 February, the corps, now as part of the First United States Army, established a bridgehead over the Roer River, which, in turn, led to the capture of the Ludendorff Bridge at Remagen, on the Rhine River, on 7 March. On 30 March, the Edersee Dam was captured intact by Task Force Wolfe of the 7th Armored Division, and the corps continued the attack to seize the Ruhr Pocket on 5 April 1945. In late April, III Corps reformed and launched a drive through Bavaria towards Austria. On 2 May 1945, III Corps was ordered to halt at the Inn River on the Austrian border, just days before V-E Day, when the German forces surrendered, bringing an end to the war in Europe.

Post-War
At the end of the war, III Corps had added campaign streamers for Northern France, Rhineland, Ardennes-Alsace, and Central Europe, had taken more than 226,102 prisoners and had seized more than 4500 sqmi of German territory. The corps had also participated in most of the critical actions from Normandy to the German-Austrian border. Its wartime commanders included Major General John Millikin and Major General James A. Van Fleet. After 13 months of occupation duty in Germany, the corps returned to Camp Polk, Louisiana, where it was inactivated on 10 October 1946.

Cold War Era
On 15 March 1951, during the height of the Korean War, III Corps was again called to active duty at Camp Roberts, California. In April 1954, III Corps moved to Fort Hood, Texas, where it participated in a number of important exercises, either as director headquarters or as a player unit. It took command of the 1st Armored Division and the 4th Armored Division. The main purpose of these operations was the testing of new doctrines, organizations, and equipment. On 5 May 1959, the corps was again inactivated.

The Berlin crisis brought III Corps back to active duty for the fourth time on 1 September 1961. Units participated in an intensive training program and were operationally ready by December 1961. In February 1962, the Department of the Army designated III Corps as a unit of the U.S. Strategic Army Corps and in September 1965, assigned III Corps to the U.S. Strategic Army Forces. Throughout much of the 1960s, III Corps and its subordinate units trained for rapid deployment to Europe in the event of an outbreak of war there.

During the Vietnam War era, the corps supervised the training and deployment of more than 137 units and detachments to Southeast Asia, including the I and II Field Force staffs. The corps also trained more than 40,000 individual replacements for units in Vietnam, for a total of over 100,000 soldiers trained. As the war in Southeast Asia ended, the corps received many units and individual soldiers for reassignment or inactivation. It was also during this period that III Corps units participated in a number of key tests and evaluations that would help determine Army organization and equipment for the next 30 years. During this era, the corps also received its distinctive unit insignia.

In July 1973, III Corps became part of the newly established Forces Command and its training, testing, and evaluation mission began to grow. For the remainder of the decade, III Corps would take part in a number of Training and Doctrine Command tests of organizations and tactical concepts, and play a key role in the fielding of new equipment. III Corps units would also participate in major exercises such as Exercise REFORGER (Return of Forces to Germany) and disaster relief operations in the United States and Central America.

In the summer of 1974, the Army decided to implement one of the recommendations of the Howze Board and created an air cavalry combat brigade. The assets of the 2nd Brigade, 1st Cavalry Division were used to create the 6th Cavalry Brigade (Air Combat). The new brigade was assigned to the III Corps as a corps asset. 1st Squadron, 6th Cavalry Regiment, was transferred to the new brigade on 21 February 1975. The brigade served as a test bed for new concepts involving the employment of attack helicopters on the modern battlefield. In 1985-85, the brigade consisted of 1st Squadron, 6th Cavalry, 4th Squadron, 9th Cavalry Regiment (4-9 CAV), and 5th and 7th Squadrons, 17th Cavalry Regiment (5-17 CAV and 7-17 CAV), all flying attack helicopters.

In the 1980s Corps units were on the leading edge of the Army's modernization effort with the introduction of new organizations and equipment including the M1 Abrams tank, M2 Bradley Fighting Vehicle, AH-64 Apache helicopter, Multiple Launch Rocket System, and Mobile Subscriber Equipment. In 1987, III Corps also conducted the largest deployment of forces to Germany since the Second World War, Exercise Reforger '87. During this time, the corps began assisting in the training and support of active and reserve component units. This support involves training guidance, resources, and the maintenance of relationships that extend to wartime affiliations.

1990s
Following the end of the Cold War, III Corps headquarters itself saw no major contingencies, however it saw numerous units under its command deploy to contingencies around the world. III Corps units were sent to Grenada, Panama, Honduras, Saudi Arabia, Kuwait, and Iraq. In the fall of 1990, two 6th Cavalry Brigade (Air Combat) units deployed to Iraq during Operation Desert Shield. One of those units was 2nd Battalion, 158th Aviation Regiment, a Chinook battalion from Fort Hood. Other corps units also provided humanitarian support for Operation Restore Hope in Somalia. III Corps elements supported Operation Joint Endeavor in Bosnia and Herzegovina as well.

It was after the Cold War that III Corps was acclimated to the role of primary counteroffensive force for the US Army. With the downsizing of other major Army formations, III Corps gained command of heavier units, including the 1st Cavalry Division while the XVIII Airborne Corps took charge of rapid-deployment for emergency contingencies, including the 101st Airborne Division and 82nd Airborne Division. III Corps took charge of the heavy units designed for large, conventional offensive actions.

Twenty-first century
In 2001, the corps was composed of the 1st Cavalry Division and the 4th Infantry Division as well as the 3rd Armored Cavalry Regiment and the 13th Corps Support Command. However, with realignment of the US Army and the return of several formations from Europe, the corps took command of the 1st Infantry Division and the 1st Armored Division as well, both of these units having been transferred from V Corps in Germany.

The corps headquarters saw its first combat deployment since the Second World War in 2004, when it deployed to Iraq for Operation Iraqi Freedom. There, III Corps headquarters assumed duties as Headquarters Multi-National Corps - Iraq, relieving V Corps. III Corps served as the administrative command for 2,500 soldiers of the Multi-National Force Iraq command element, providing operational direction into 2005, when it was returned to Fort Hood, relieved by XVIII Airborne Corps.

III Corps Artillery was inactivated on 8 September 2006. Henceforth the field artillery brigades, soon to become Fires Brigades, would be assigned to the corps and division headquarters directly. In 2007, the corps returned to Iraq for a second time to serve as commanding headquarters for Multi-National Corps Iraq. During this 15-month deployment, the corps took command of the force when it was at its largest yet in the war dur to the Iraq War troop surge conducted that year. The corps conducted a similar mission to its first deployment, focusing on providing personnel management, training, communications, convoy escort, and other duties to support the commanding elements of Multi-National Force Iraq. III Corps fulfilled this mission until February 2008, when it returned home, again relieved by XVIII Airborne Corps.

In 2009, the corps began a number of training initiatives with the Republic of Korea Army. These included Operation Key Resolve, a command post exercise simulating major, high intensity combat operations. The exercises were held in Yongin, South Korea. These operations were designed to keep the corps familiar with commanding during large-scale conventional warfare, as opposed to counter-insurgency tactics it employed during its two tours in Iraq. Upon return to the United States, the corps conducted similar exercises at Fort Hood.

On 5 November 2009, a gunman opened fire in the Soldier Readiness Center of Fort Hood, killing 13 people and wounding 30 others. Nidal Malik Hasan, a Muslim U.S. Army Major and psychiatrist, was alleged to be the gunman. He was felled and then arrested by civilian police officers Sergeant Mark Todd & Sergeant Kimberly Munley. Much of the subsequent investigation was handled by III Corps, as the soldiers killed were under the corps' chain of command.

III Corps has for many years participated in an exchange program which sees a Canadian Army officer appointed as a Deputy Commanding General. Notably, Peter Devlin deployed with the corps to Iraq in 2005. As of 2011, the Canadian officer was Brigadier-General Dean Milner.

Organization
III Corps, Fort Hood
 * III Corps Special Troops Battalion, Fort Hood
 * 1st Armored Division, Fort Bliss
 * 1st Cavalry Division, Fort Hood
 * 1st Infantry Division, Fort Riley
 * 4th Infantry Division, Fort Carson
 * 3rd Armored Cavalry Regiment, Fort Hood
 * 41st Fires Brigade, Fort Hood
 * 75th Fires Brigade, Fort Sill
 * 212th Fires Brigade, Fort Bliss
 * 214th Fires Brigade, Fort Sill
 * 36th Engineer Brigade, Fort Hood
 * 504th Battlefield Surveillance Brigade, Fort Hood
 * 89th Military Police Brigade, Fort Hood
 * 13th Sustainment Command, Fort Hood

Other major units stationed along the III Corps units are:
 * 4th Maneuver Enhancement Brigade, Fort Leonard Wood
 * 6th Air Defense Artillery Brigade, Fort Sill (United States Army Air Defense Artillery School)
 * 32nd Army Air & Missile Defense Command, Fort Bliss
 * 11th Air Defense Artillery Brigade, Fort Bliss
 * 31st Air Defense Artillery Brigade, Fort Sill (Was assigned to III Corps and once was based at Fort Hood)
 * 69th Air Defense Artillery Brigade Fort Hood
 * 48th Chemical Brigade, Fort Hood
 * 71st Ordnance Group (EOD), Fort Carson

The corps’s divisions are supported by the following sustainment brigades, which are under direct command of FORSCOM:
 * 1st Sustainment Brigade at Fort Riley supporting the 1st Infantry Division
 * 4th Sustainment Brigade at Fort Hood supporting the 1st Cavalry Division
 * 15th Sustainment Brigade at Fort Bliss supporting the 1st Armored Division
 * 43rd Sustainment Brigade at Fort Carson supporting the 4th Infantry Division

Honors
The corps received five campaign streamers in World War I and four campaign streamers in World War II. It also received two campaign streamers and two unit awards during the War on Terrorism.