 In April 1983, the Commandant of the Marine Corps approved the original Marine Air-Ground Task Force (MAGTF) Headquarters concept, providing for the sourcing of two Marine Amphibious Unit (MAU) headquarters from each Marine Amphibious Brigade headquarters.The Commandant directed the establishment of two additional MAU headquarters in November 1985.As a result, the Headquarters, 15th Marine Amphibious Unit was activated 1 July 1987 at Camp Pendleton.