 After graduation from the Command and General Staff School at Fort Leavenworth, Kansas in September 1945 he served as a battalion commander until relieved from active duty as a major in December 1945.Warburton was admitted to the Delaware Bar in absentia in 1942 and began a practice following his return from the Army in 1946.He served as city solicitor for Wilmington, Delaware from 1949 until 1952.