The Twelfth United States Army Group was the largest and most powerful United States Army formation ever to take to the field, commanding four field armies at its peak in 1945: First United States Army, Third United States Army, Ninth United States Army, and Fifteenth United States Army. The order of battle across the four armies comprised 12 corps, containing a total of 48 divisions. Formed eight days after the Normandy landings, it initially controlled the First and the Third US Armies. Through various configurations in 1944 and 1945, the Twelfth US Army Group controlled the majority of American forces on the Western Front. It was commanded by General Omar Bradley with its headquarters established in London on 14 July 1944.

During the first week of the Normandy landings and the Battle of Normandy, Bradley's First US Army formed the right wing of the Allied lines. They were joined during July by the Third US Army, under the command of General George S. Patton, to form the Twelfth Army Group. Twelfth Army Group became operational in France on 1 August 1944. With General Omar Bradley assuming command of the Twelfth Army Group, Lieutenant General Courtney Hodges assumed command of the First Army. In addition, the USAAF's Ninth Air Force (not included in the 1.3 million soldiers figure) was attached to support the field armies of the Twelfth Army Group.

Until 1 September 1944, when General Dwight D. Eisenhower assumed overall command of the Allied land forces in Northwest Europe, the US forces in Normandy were included with the British Second Army and the First Canadian Army in the British headquarters formation 21st Army Group, commanded by General Bernard Montgomery.

After the breakout from the beach-head at Normandy, the Twelfth Army Group formed the center of the Allied forces on the Western Front. To the north was the British 21st Army Group (the First Canadian and British Second) and, to the south, advancing from their landing on the Mediterranean coast, was the Sixth United States Army Group (Seventh United States Army and French First Army).

As the Twelfth advanced through Germany in 1945, it grew to control four United States field armies: the First, the Third, the Ninth and the Fifteenth. By V-E Day, the Twelfth Army Group was a force that numbered over 1.3 million men.CSI REPORT No. 6, Larger units: Theater Army – Army Group – Field Army, Combat Studies Institute, U.S. Army Command and General Staff College, Fort Leavenworth, Kansas, January 1985

Twelfth Army Group was inactivated on 12 July 1945 upon Bradley's departure to become Director of the Veterans Administration. Its subordinate elements then became directly subordinate to United States Army Europe.

Staff

+ Headquarters Twelfth United States Army GroupCommanding General and Chiefs of Staff Sections Position 1 August 1944 8 May 1945Commanding General Lieutenant General Omar N. Bradley General Omar N. BradleyChief of Staff Major General Leven C. Allen Major General Leven C. AllenDeputy Chief of Staff Brigadier General Robert W. Hasbrouck Brigadier General Henry B. LewisSecretary, General Staff Lieutenant Colonel Eldon L. Bailey Colonel Eldon L. BaileyG-1 (Personnel) Colonel Joseph J. O'Hare Brigadier General Joseph O'HareG-2 (Intelligence) Brigadier General Edwin L. Sibert Brigadier General Edwin L. SibertG-3 (Operations and training) Brigadier General A. Franklin Kibler Brigadier General A. Franklin KiblerG-4 (Logistics) Brigadier General Raymond G. Moses Brigadier General Raymond G. MosesG-5 (Civil-military operations) Colonel Cornelius E. Ryan Brigadier General Cornelius E. RyanAdjutant General Brigadier General Henry B. Lewis Colonel Charles R. LandonArtillery Officer Brigadier General John H. Hinds Colonel Thomas B. HedekinArmored Colonel Edwin K. Wright Colonel Edwin K. WrightChaplain Lieutenant Colonel Morgan J. O'BrienChemical Colonel John C. MacArthur Colonel Patrick F. PowersEngineer Colonel Patrick H. Timothy Brigadier General Patrick H. TimothyFinance Lieutenant Colonel Paul G. Hommeyer Major Eugene R. MeltonHeadquarters Commandant Colonel Harry J. Karakas Colonel Harry J. KarakasInspector General Lieutenant Colonel Walter B. Cramer Colonel Frank G. RinglandJudge Advocate Colonel Claude B. Mickelwait Colonel Claude B. MickelwaitOrdnance Colonel Harold A. Nisley Brigadier General Harold A. Nisley Colonel Clifford R. Powell Colonel Francis J. FitzgeraldProvost Marshal Colonel Claud E. Stadtman Colonel Claud E. StadtmanQuartermaster Colonel James W. Younger Brigadier General James W. YoungerSignal Colonel Garland C. Black Brigadier General Garland C. BlackSpecial Service Lieutenant Colonel Francis E. Conder Colonel Thomas M. CrawfordSurgeon Colonel Alvin L. Gorby Colonel Alvin L. GorbyTransportation Colonel Calvin L. Whittle Colonel Calvin L. WhittleCommanding General, Special Troops Brigadier General Charles R. Doran Brigadier General Charles R. Doran

Order of battle – 8 May 1945

12th Army Group – General Omar N. Bradley First Army – General Courtney H. Hodges 78th Infantry Division – Major General Edwin P. Parker Jr. VII Corps – Lieutenant General J. Lawton Collins 3rd Armored Division – Brigadier General Doyle O. Hickey 9th Infantry Division – Major General Louis A. Craig 69th Infantry Division – Major General Emil F. Reinhardt 104th Infantry Division – Major General Terry de la Mesa Allen Sr. VIII Corps – Major General Troy H. Middleton 6th Armored Division – Major General Robert W. Grow 76th Infantry Division – Major General William R. Schmidt 87th Infantry Division – Major General Frank L. Culin Jr. 89th Infantry Division – Major General Thomas D. Finley Third Army – General George S. Patton Jr. 4th Infantry Division – Major General Harold W. Blakeley 70th Infantry Division – Major General Allison J. Barnett III Corps – Major General James Van Fleet 14th Armored Division – Major General Albert C. Smith 99th Infantry Division – Major General Walter E. Lauer V Corps – Major General Clarence R. Huebner 9th Armored Division – Major General John W. Leonard 16th Armored Division – Brigadier General John L. Pierce 1st Infantry Division – Major General Clift Andrus 2nd Infantry Division – Major General Walter M. Robertson 97th Infantry Division – Brigadier General Milton B. Halsey XII Corps – Major General Stafford LeRoy Irwin 4th Armored Division – Major General William M. Hoge 11th Armored Division – Major General Holmes E. Dager 5th Infantry Division – Major General Albert E. Brown 26th Infantry Division – Major General Willard S. Paul 90th Infantry Division – Major General Herbert L. Earnest XX Corps – Major General Walton H. Walker 13th Armored Division – Major General John Millikin 65th Infantry Division – Major General Stanley E. Reinhart 71st Infantry Division – Major General Willard G. Wyman 80th Infantry Division – Major General Horace L. McBride Ninth Army – Lieutenant General William H. Simpson XIII Corps – Major General Alvan C. Gillem, Jr. 35th Infantry Division – Major General Paul W. Baade 84th Infantry Division – Major General Alexander R. Bolling 102nd Infantry Division – Major General Frank A. Keating XVI Corps – Major General John B. Anderson 29th Infantry Division – Major General Charles H. Gerhardt 75th Infantry Division – Major General Ray E. Porter 79th Infantry Division – Major General Ira T. Wyche 95th Infantry Division – Major General Harry L. Twaddle XIX Corps – Major General Raymond S. McLain 2nd Armored Division – Major General Isaac D. White 8th Armored Division – Major General John M. Devine 30th Infantry Division – Major General Leland S. Hobbs 83rd Infantry Division – Major General Robert C. Macon Fifteenth Army – Lieutenant General Leonard T. Gerow 66th Infantry Division – Major General Herman F. Kramer 106th Infantry Division – Major General Donald A. Stroh XXII Corps – Major General Ernest N. Harmon 17th Airborne Division – Major General William M. Miley 94th Infantry Division – Major General Harry J. Malony XXIII Corps – Major General Hugh J. Gaffey 28th Infantry Division – Major General Norman D. Cota XVIII Airborne Corps (attached to 21st Army Group) – Major General Matthew B. Ridgway 5th Armored Division – Major General Lunsford E. Oliver 7th Armored Division – Major General Robert W. Hasbrouck 8th Infantry Division – Major General Bryant E. Moore 82nd Airborne Division – Major General James M. Gavin

Source: Bradley, Omar, A Soldier's Story, New York: Henry Holt and Company (1950), pp. 557–561

References and notes

External links Military situation maps produced by the Engineering Section of the 12th Army Group – Library of Congress Omar Nelson Bradley, Lt. General FUSAG 12TH AG – Omar Bradley's D-Day June 6, 1944 Maps restored, preserved and displayed at Historical Registry