This is the American Expeditionary Forces on the Western Front order of battle. The American Expeditionary Forces (AEF) consisted of the United States Armed Forces (mostly the United States Army) that were sent to Europe in World War I to support the Allied cause against the Central Powers. During the United States campaigns in World War I the AEF fought in France alongside French and British allied forces in the last year of the war, against Imperial German forces. Some of the troops fought alongside Italian forces in that same year, against Austro-Hungarian forces. Late in the war American units also fought in Siberia and North Russia.Votaw (2013), p. 62.

President Woodrow Wilson created the AEF in May 1917, originally appointing Major General John J. Pershing, who was later promoted to general, as commander. Barely any American troops were sent to Europe in 1917, since Pershing ordered all AEF forces to be well-trained before going overseas.Coffman (1998).

The troop ships used to transport the AEF were, at first, any ships that were available. Cruisers, German ships seized by the Navy, ships borrowed from the Allies, and many other ships were used to ship troops to Europe from ports in New York, New Jersey, and Virginia. By June 1917, only 14,000 soldiers had made it to the front lines, but by May 1918 over two million American troops had reached Europe, with around half of them on the front lines.Pershing (1931).

The AEF helped the French Army on the Western Front during the Aisne Offensive (at Château-Thierry and Belleau Wood) in June 1918, and fought its major actions in the Saint-Mihiel and Meuse–Argonne Offensives in late 1918.Votaw (2013), p. 6. Organized into two field armies (a third was forming as the war ended), it had a total strength of about two million men in Europe by the time of the Armistice.Grotelueschen (2007), pp. 13 & 343. Planned to eventually consist of nine corps,Army War College Historical Section (1988a), p. v. a total of five AEF corps and two unassigned divisions were in the field by September 1918.Gibbons (2014), p. 388. It was subsequently involved in the Occupation of the Rhineland.Pawley (2008) pp. 32–33

First Army The First Army was officially organized and activated by General John J. Pershing on 4 July 1918, although it was technically formed when the United States entered the World War in 1917. It served in the Saint-Mihiel offensive, Lorraine offensive, Champagne offensive, and the Meuse–Argonne Offensive. It was finally demobilized and moved back to the United States on 30 April 1919.Army War College Historical Section (1988a), pp. 81–149.

First Army (structure as of the Battle of Saint-Mihiel)(30 August to 16 September 1918)General John J. Pershing (10 August 1918 – 16 October 1918) Name Commander NotesI Corps Major General Hunter LiggettFormed 15–20 January 1918IV Corps Major General George Windle ReadFormed on 20 June 1918V Corps Major General William M. WrightFormed on 7–12 July 1918 Lieutenant General Ernest Joseph BlondlatFormed in June 1915Sources: Unless otherwise cited, the source is

Second Army The Second Army was activated on 9 September and was organized by Colonel Stuart Heintzelman. On 12 October 1918, General Robert Lee Bullard took command of the Second Army and Heintzelman became his chief of staff. The formation was committed to the Lorraine offensive on 26 October. It attacked in the Lorraine area, and also around Saint-Mihiel, before later recapturing and liberating the Duchy of Luxemburg. It was demobilized on 15 April 1919, after the war had ended.Army War College Historical Section (1988a), pp. 150–169 Second Army (structure as of the period from 16 October 1918 to 11 November 1918) Lieutenant General Robert Lee Bullard (12 October 1918 – 15 April 1919) Name Commander NotesIV Corps Major General George Windle ReadFormed on 20 June 1918VI Corps Major General Charles C. BallouFormed on 1 August 1918VII Corps Major General Omar BundyFormed on 19 August 1918 Major General Henri Edouard ClaudelFormed in June 1915XVII Corps (France) Lieutenant General Frederio Emile Amedee HellotPart of the peacetime French Army in 1914Sources: Unless otherwise cited, the source is

Third Army Following the defeat of Germany, Allied forces occupied the Rhineland under the terms of the Armistice. The United States provided around 240,000 men in nine veteran divisions, nearly a third of the total occupying force, for this task. These troops were organized into the Third Army, which was established by Pershing specifically for the purpose, under the command of Major General Joseph Dickman.

Third Army (structure as of the period from 17 to 22 November 1918) Major General Joseph T. Dickman (15 November 1918 – 29 April 1919) Name Commander NotesIII Corps Major General William M. WrightFormed on 16 May 1918IV Corps Major General George Windle ReadFormed on 20 June 1918Sources: Unless otherwise cited, the source is

I Corps

Lieutenant General Hunter Liggett took command of I Corps when it was created, almost one year after the Americans entered the war. It served through most of the battles that the American Expeditionary Forces fought on the Western Front.Lineage and Honors Information: I Corps (2009).

Assisted by the French XXXII Corps, I Corps was organized and activated on 15–20 January 1918. I Corps saw its first major action at the Battle of Chateau-Thierry, while seeing its first offensive action several days later at the Second Battle of the Marne. After serving briefly in the defensive sectors of Lorraine and Champagne, I Corps later served in the Battle of Saint-Mihiel and the Meuse–Argonne Offensive.I Corps History: World War I (2009). It was finally demobilized on 25 March 1919.Army War College Historical Section (1988a), p. 219.

I Corps (structure as of the Battle of Saint-Mihiel)(10 August to 17 September 1918)Lieutenant General Hunter Liggett Name Commander Units Notes1st Infantry Division Major General Charles P. Summerall 1st Infantry BrigadeHenry (2012), p. 11. 16th Infantry Regiment 18th Infantry Regiment 2nd Machine Gun Battalion 2nd Infantry Brigade 26th Infantry Regiment 28th Infantry Regiment 3rd Machine Gun Battalion 1st Field Artillery Brigade 5th Field Artillery Regiment 6th Field Artillery Regiment 7th Field Artillery Regiment 1st Trench Mortar Battery2nd Infantry Division Brigadier General Charles A. Doyen, USMC 3rd Infantry Brigade 9th Infantry Regiment 23rd Infantry Regiment 5th Machine Gun Battalion 4th Marine Brigade 5th Marine Regiment 6th Marine Regiment 6th Machine Gun Battalion (USMC) 2nd Field Artillery Brigade 12th Field Artillery Regiment 15th Field Artillery Regiment 17th Field Artillery Regiment 2nd Trench Mortar Battery Division included troops of the United States Marine Corps (USMC)Army War College Historical Section (1988b), p. 25.26th Infantry Division Major General Clarence Ransom Edwards 51st Infantry Brigade 101st Infantry Regiment 102nd Infantry Regiment 102 Machine Gun Battalion 52nd Infantry Brigade 103 Infantry Regiment 104th Infantry Regiment 103 Machine Gun Battalion 51st Field Artillery Brigade 101st Field Artillery Regiment 102nd Field Artillery Regiment 103rd Field Artillery Regiment 101st Trench Mortar Battery32nd Infantry Division Major General James Parker 63rd Infantry Brigade 125th Infantry Regiment 126th Infantry Regiment 120th Machine Gun Battalion 64th Infantry Brigade 127th Infantry Regiment 128th Infantry Regiment 121st Machine Gun Battalion 57th Field Artillery Brigade 119th Field Artillery Regiment 120th Field Artillery Regiment 121st Field Artillery Regiment 107th Trench Mortar Battery41st Infantry DivisionVotaw (2013), pp. 30–32. was separated into multiple other units before a commander could be announced 81st Infantry Brigade 161st Infantry Regiment 162nd Infantry Regiment 147th Machine Gun Battalion 82nd Infantry Brigade 163rd Infantry Regiment 164th Infantry Regiment 148th Machine Gun Battalion 66th Field Artillery Brigade 146th Field Artillery Regiment 147th Field Artillery Regiment 148th Field Artillery Regiment 116th Trench Mortar Battery42nd Infantry Division Major General William Abram Mann 83rd Infantry Brigade 165th Infantry Regiment 166th Infantry Regiment 150th Machine Gun Battalion 84th Infantry Brigade 167th Infantry Regiment 168th Infantry Regiment 151st Machine Gun Battalion 67th Field Artillery Brigade 149th Field Artillery Regiment 150th Field Artillery Regiment 151st Field Artillery Regiment 117th Trench Mortar BatterySources: Unless otherwise cited, the source is

II Corps II Corps was organized in January 1918 with its headquarters being located in Montreuil, France. It moved to the Western Front in February 1918, and served in the Second Battle of the Somme and the Third Battle of Albert. It mostly served alongside the New Zealand Division and the Australian Corps.Gibbons (2014), p. 91. After the Armistice, II Corps was reassigned to the Third Army's control, before being demobilized on 1 February 1919.Army War College Historical Section (1988a), p. 235.

II Corps (structure as of Post-Armistice activities)(19 November 1918 to 31 January 1919)Lieutenant General Robert Lee Bullard Name Commander Units27th Infantry Division Major General John F. O'Ryan 53rd Infantry Brigade 105th Infantry Regiment 106th Infantry Regiment 105th Machine Gun Battalion 54th Infantry Brigade 107th Infantry Regiment 108th Infantry Regiment 106th Machine Gun Battalion 52nd Field Artillery Brigade 104th Field Artillery Regiment 105th Field Artillery Regiment 106th Field Artillery Regiment 102nd Trench Mortar Battery28th Infantry Division Major General Charles H. Muir 55th Infantry Brigade 109th Infantry Regiment 110th Infantry Regiment 109th Machine Gun Battalion 56th Infantry Brigade 111th Infantry Regiment 112th Infantry Regiment 110th Machine Gun Battalion 53rd Field Artillery Brigade 107th Field Artillery Regiment 108th Field Artillery Regiment 103rd Trench Mortar Battery30th Infantry Division Major General Edward Mann Lewis 59th Infantry Brigade 117th Infantry Regiment 118th Infantry Regiment 113th Machine Gun Battalion 60th Infantry Brigade 119th Infantry Regiment 120th Infantry Regiment 114th Machine Gun Battalion 55th Field Artillery Brigade 113th Field Artillery Regiment 114th Field Artillery Regiment 115th Field Artillery Regiment 105th Trench Mortar Battery35th Infantry Division Major General Peter E. Traub 69th Infantry Brigade 137th Infantry Regiment 138th Infantry Regiment 129th Machine Gun Battalion 70th Infantry Brigade 139th Infantry Regiment 140th Infantry Regiment 130th Machine Gun Battalion 60th Field Artillery Brigade 128th Field Artillery Regiment 129th Field Artillery Regiment 130th Field Artillery Regiment 110th Trench Mortar Battalion77th Infantry Division Major General George B. Duncan 153rd Infantry Brigade 305th Infantry Regiment 306th Infantry Regiment 305th Machine Gun Battalion 154th Infantry Brigade 307th Infantry Regiment 308th Infantry Regiment 306th Machine Gun Battalion 152nd Field Artillery Brigade 304th Field Artillery Regiment 305th Field Artillery Regiment 306th Field Artillery Regiment 302nd Trench Mortar Battery82nd Infantry Division Major General William P. Burnham 163rd Infantry Brigade 325th Infantry Regiment 326th Infantry Regiment 319th Machine Gun Battalion 164th Infantry Brigade 327th Infantry Regiment 328th Infantry Regiment 320th Machine Gun Battalion 157th Field Artillery Brigade 319th Field Artillery Regiment 320th Field Artillery Regiment 321st Field Artillery Regiment 307th Trench Mortar BatterySources: Unless otherwise cited, the source is

III Corps