"King, in addition to heading the Navy, served as a member of the U.S. Joint Chiefs of Staff, which also included General George C. Marshall, Army Chief of Staff, General Henry H. ("Hap") Arnold, Chief of Staff of the Army Air Forces, and, later, Admiral William D. Leahy, Chief of Staff to the President. The U.S. Joint Chiefs of Staff and the British Imperial Chiefs of Staff, when meeting together, comprised the Combined Chiefs of Staff, the senior executive body controlling Allied military operations. The CCS delegated most of the control of Pacific theater operations to the JCS, who for this function relied heavily on the advice of Admiral King."