United States Army Services of Supply in the context of "San Francisco Port of Embarkation"

The Army Service Forces was one of the three autonomous components of the United States Army during World War II, the others being the Army Air Forces and Army Ground Forces, created on 9 March 1942. By dividing the Army into three large commands, the Chief of Staff, General George C. Marshall, drastically reduced the number of officers and agencies reporting directly to him. The Army Service Forces brought together elements of five different components of the Army: elements of the War Department General Staff (WDGS), especially its G-4 division (responsible for logistics); the Office of the Under Secretary of War; the eight administrative bureaus; the nine corps areas, which became service commands; and the six supply arms and services, which became known as the technical services. The Army Service Forces was initially known as the United States Army Services of Supply but the name was changed on 12 March 1943, as it was felt that the term "supply" did not accurately describe the broad range of its activities. The Army Service Forces was abolished on 11 June 1946 and most of its functions were taken over by the War Department General Staff.

For most of its existence, the Army Service Forces was commanded by General Brehon B. Somervell, with Lieutenant General Wilhelm D. Styer as his chief of staff. After Styer left for the Pacific, he was succeeded by Major General LeRoy Lutes on 18 April 1945. Brigadier General Lucius D. Clay was the Deputy Chief of Staff for Requirements and Resources, and as such he was responsible for the development of the Army Supply Program, the operation of the Lend-Lease program, and liaison with the War Production Board concerning the allocation of raw materials. Although he had his own logistics staff in the G-4 division of the War Department General Staff, it was to Somervell and Styer that Marshall turned to for advice on logistical matters, and it was Somervell who attended the important wartime conferences.

The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and de facto aerial warfare service branch of the United States during and immediately after World War II (1941–1947). It was created on 20 June 1941 as successor to the previous United States Army Air Corps and is the direct predecessor of the United States Air Force, today one of the six armed forces of the United States. The AAF was a component of the United States Army, which on 2 March 1942 was divided functionally by executive order into three autonomous forces: the Army Ground Forces, the United States Army Services of Supply (which in 1943 became the Army Service Forces), and the Army Air Forces. Each of these forces had a commanding general who reported directly to the Army chief of staff.

The AAF administered all parts of military aviation formerly distributed among the Air Corps, General Headquarters Air Force, and the ground forces' corps area commanders and thus became the first air organization of the U.S. Army to control its own installations and support personnel. The peak size of the AAF during World War II was over 2.4 million men and women in service and nearly 80,000 aircraft by 1944, and 783 domestic bases in December 1943. By "V-E Day", the Army Air Forces had 1.25 million men stationed overseas and operated from more than 1,600 airfields worldwide.