Decker was commissioned a second lieutenant of infantry in June 1924, and began his army service with the
26th Infantry Regiment, then stationed at
Plattsburg Barracks in upstate New York. In 1928, he was sent to Hawaii, where he served with the
35th Infantry Regiment until 1931. He was promoted to first lieutenant in April 1930. After attending advanced infantry training at the
Infantry School at
Fort Benning in 1932, he remained at Fort Benning with the
29th Infantry Regiment until 1935, followed by service at
Vancouver Barracks, near
Portland, Oregon, with the
7th Infantry Regiment from 1935 to 1936 (during which time he was promoted to captain, in August 1935). In 1936, Decker was sent to the Command and General Staff School at
Fort Leavenworth, from which he graduated in 1937. Subsequently, he served with the
10th Infantry Regiment at
Fort Thomas, Kentucky, and
Fort McClellan, Alabama, and the
9th Infantry Regiment at
Fort Bragg, North Carolina. In 1940 he took command of Headquarters Company,
I Corps, at
Fort Jackson, South Carolina, and was assistant supply and logistics officer, 1940–1941. In 1941 came a flurry of promotions: to temporary major (January), permanent major (June), and temporary lieutenant colonel (December). He was sent to Washington, D.C., to serve on the War Department General Staff, where he was assigned to the Office of the Assistant Chief of Staff for Supply. He was promoted to temporary colonel in October 1942 and became deputy chief of staff of the Third Army,
Fort Sam Houston, Texas. He was then sent overseas to the Southwest Pacific, where he became deputy chief of staff and then chief of staff of the
Sixth Army, a position he held through the end of World War II. He had been promoted to temporary brigadier general in August 1944 and major general in June 1945, and participated in Sixth Army operations in New Guinea, the Solomon Islands and the Philippines. and General
J. Lawton Collins, Army Chief of Staff, in
the Pentagon in routine sessions, June 5, 1952. Major General George Decker is stood second from the left, between Major General
Edwin K. Wright (left) and Major General
Lester J. Whitlock (right). Decker returned to Washington in 1946 to Headquarters, Army Ground Forces and Headquarters, Army Service Forces, but soon went back to the Pacific as deputy commanding general and chief of staff of United States Forces, Middle Pacific, Hawaii, from 1946 to 1948. Decker became commanding general of the
5th Infantry Division in 1948, and in 1950 was assigned to the Office of the Comptroller of the Army as Chief of the Budget Division. Promoted to temporary lieutenant general in 1952, he became
Comptroller of the United States Army from 1952 to 1955. He was promoted to permanent brigadier general in April 1953 and permanent major general in July 1954. In 1955, he went to Germany as commanding general of
VII Corps at Stuttgart, and was promoted to temporary general in May 1956. From 1956 to 1957, Decker was deputy commander-in-chief of the
United States European Command at its headquarters in Rocquencourt, outside Paris, France. From 1957 to 1959 he was commander-in-chief,
United Nations Command, and commanding general,
United States Forces Korea and
Eighth United States Army. Decker was appointed
Vice Chief of Staff of the United States Army in 1959 and on October 1, 1960, became
Chief of Staff of the United States Army, serving in that capacity until September 30, 1962. Highlights of Decker's tenure were supervising augmentations to meet the crisis in Berlin (prompted by the construction of the
Berlin Wall in 1961), increasing special warfare forces, initiating new divisional and forward depot concepts, and expanding the army to sixteen divisions. Decker retired at the end of his tenure. == Later life ==