Calvin was drafted into the Army on 2 June 1941. He received a promotion to Corporal on 1 Sep, Sergeant on 5 Sep, and Staff Sergeant on 25 Sep 1941. He was then commissioned with a promotion to 2nd Lieutenant on 10 Jun 1942 and the subsequent promotions followed: 1st Lt Feb 1943, Capt Feb 1944, Maj Aug 1945, Lt Col 1952, and Colonel 1961. Calvin participated in all five European campaigns, including Normandy, and was a member of General Eisenhower's staff in London. 12 years of his career were spent in foreign countries: England, France, Belgium, Germany, and Japan. He received ten military awards and decorations. After retirement, Calvin was the general manager of an electronics company. He is married to Carolyn J. Campbell.