Following the Battle of Peleliu, Campbell served simultaneously as Peleliu Island Commander. He was succeeded by Brigadier General Christian F. Schilt in March 1945 and returned to the United States. Campbell was appointed commanding general of the 9th Marine Aircraft Wing and Marine Corps Air Station Cherry Point. He served in this capacity until his retirement in November 1947. Campbell was advanced to the rank of major general on the retired list for having been specially commended in combat.