In 1939 and early 1940 the training of soldiers and troop units for ground combat was divided among the four of the Army''s "arms"--the Infantry, the Field Artillery, the Coast Artillery Corps, and the Cavalry--each headed, in Washington, D.C., by an Office of the Chief of the arm. In 1939 these arms were supervised at the General Staff level by the Chief of Staff, mainly through the Operations and Training Division, G-3. In July 1940, the General Headquarter United States Army, also known as GHQ, was established as an additional staff organization for ground-force training affairs.
As part of the general reorganization of the War Department, in March 1942, the Army Ground Forces, known also as AGF, was established as a means of consolidating ground-force training responsibilities. It was created on February 28, 1942 by Executive Order Number 9082 "Reorganizing the Army and the War Department" , and War Department Circular No.59, dated March 2, 1942. The new AGF Headquarters replaced GHQ and the chiefs of the four arms, whose offices were simultaneously discontinued. At the same time AGF inherited in the field the service schools and service boards of those arms, and later it acquired other field organizations.
These ground-force training functions and activities included these phases: training of ground troops as individual combat soldiers; organization of such troops into combat divisions and other tactical units; training of such combat units; and training in the use of appropriate ground weapons and equipment. Some of these training responsibilities were not handled exclusively, however, within AGF and ots predecessor organizations. Thus, some functions were shared with the Army Service Forces and its Technical Services, notably the "basic" training of troops during the period immediately after their induction and the training of special combat troops such as Chemical Warfare mortar battalions and Combat Engineer troops. Otrher types of ground training, especially the training of noncombat troops for supply, maintenance, and other service functions, were a responsibility of the various Technical Services of the Army Service Forces.
Besides its major function of tactical training, AGF performed certain duties closely related to the training processes. AGF and its predecessor arms assisted the General Staff and the Army Service Forces and its Technical Services in frmulating quality and quantity requirements for ground weapons and ground equipment. This included requirements both of AGF''s troops in training and of the ground Armies that operated in the combat theaters. AGF also shared with Army Service Forces the testing of new and improved ground weapons and equipment, and with the General Staff the formulation of tactical doctrine and operational techniques used in land warfare. From June 1946 until March 1948 it exercised command over the six field armies within the continental United States.
Commanding Generals of AGF were Lieutenant General Leslie J. McNair, 1942 - 44; Lieutenant GeneraL Ben Lear, 1944-45; General Joseph W. Stilwell, 1945; and General Jacob L. Devers, 1945-48
Army Ground Forces was abolished by Department of the Army Circular 64, March 10, 1948, and succeeded by Army Field Forces.
