During World War I, Devers was at Fort Sill, Oklahoma. In 1919, he served in the occupation of Germany and attended the French Artillery School at Treves before again teaching at West Point. Devers graduated from the General Staff College (1925) and the Army War College (1933). From 1936 to 1939 he was at West Point, where he was advanced to colonel.
After World War II began in Europe in 1939, Army Chief of Staff General George C. Marshall ordered Devers to place the Panama Canal Zone on a wartime footing. The next year, Devers was promoted to brigadier general. Following staff duty in Washington, he commanded the 9th Infantry Division at Fort Bragg, North Carolina. Supervising the rapid expansion of this base, he earned promotion to major general.
Known for his ability to train troops, Devers in July 1941 took command of the Armored Force at Fort Knox, Kentucky, and there he supervised the rapid expansion of U.S. armored forces. He soon became an enthusiastic advocate of mobile combined-arms warfare. Devers was promoted to lieutenant general in September 1942.
In May 1943, Devers took charge of U.S. Army ground forces in the European Theater of Operations (ETOUSA). He supervised the rapid U.S. buildup in Britain and hoped to lead the cross-Channel invasion. Instead, he was sent at the end of 1943 to the Mediterranean as deputy supreme Allied commander there, replacing General Dwight D. Eisenhower. On 15 September 1944, Devers finally received the combat command he had long sought: the Sixth Army Group of 23 divisions, consisting of Lieutenant General Alexander Patch's Seventh Army and General Jean de Lattre de Tassigny's First French Army, which had invaded southern France in Operation dragoon. In March 1945, Devers was promoted to general and that same month his Sixth Army Group crossed the Rhine and drove into southern Germany and Austria, where he accepted the surrender of German forces on 6 May.
Devers commanded U.S. Army Ground Forces from 1945 to 1949 and retired in September 1949. He died in Washington, D.C., on 15 October 1979.
Brent B. Barth Jr.
Devers, Jacob L. Report of Activities: Army Ground Forces. Washington, DC: U.S. Army, 1946.; Perret, Geoffrey. There's a War to Be Won: The United States Army in World War II. New York: Random House, 1991.; Weigley, Russell F. Eisenhower's Lieutenants: The Campaigns of France and Germany, 1944–1945. Bloomington: Indiana University Press, 1981.; Wilt, Alan F. The French Riviera Campaign of August 1944. Carbondale: Southern Illinois University Press, 1981.