After graduating from the University of Louisville School of Medicine, Kentucky, in 1939 with a doctor of medicine degree, Robert Patterson was called from residency training to active military duty in October 1940 with the Michigan National Guard and in 1943 he went to the European Theater of Operations as assistant wing surgeon, 100th Fighter Wing. After serving in the Army Air Forces in World War II, he transferred to the U.S. Air Force when it became a separate branch of service in 1947. From 1972 to 1975 he served as the 8th Surgeon General of the Air Force. He retired in 1975 as a U.S. Air Force Lieutenant General.