Brigadier General John Calhoun enlisted in the Tennessee National Guard on 6 December 1938. He was commissioned a Second Lieutenant upon graduation from the Infantry Officer Candidate School 27 September 1942. He served on active duty until 6 December 1945. He participated in five campaigns in the European Theater of Operations. | He continued in the military as a member of the Officers' Reserve Corps. He was appointed a First Lieutenant in the Army National Guard on 9 December 1946 and was assigned to the 278th Regimental Combat Team. Colonel Calhoun served on active duty from 1 August 1950 until 3 September 1952 with this unit. | Upon reorganization of the 278th RCT, he was employed as Staff Assistant for this organization and continued in this capacity until May 1966. At this time, he resigned as a Guard Technician to accept appointment as a Probation Officer with the Federal District Court at Knoxville, Tennessee. | General Calhoun was promoted to Colonel on 12 May 1966 and assigned as Commander of the First Brigade, 30th Armored Division. For a short time in 1968 General Calhoun served as Operations Officer with the State Headquarters Detachment in Nashville, Tennessee. He returned to command 30th Armored Division Support Command with Headquarters in Knoxville, Tennessee after the February 1968 reorganization. He was appointed assistant Division Commander, 30th Armored Division on 3 August 1971 and received his federal recognition as a Brigadier General on 4 August 1972. He was appointed Division Commander, 30th Armored Division on 31 May 1973 and remained in this capacity until the Division was deactivated on 31 October 1973. At this time he became Commander of the 278th Provisional Infantry Brigade (Mech), Knoxville, Tennessee. | General Calhoun holds the Purple Heart w/2 Oak Leaf Clusters, Bronze Star Medal w/ Oak Leaf Cluster and V device for Valor, Combat Infantryman Badge, National Defense Service Medal, French Fourragere, World War II Victory Medal, African European Middle Eastern Theater Medal with Battalion participation awards. He also holds the Tennessee Army National Commendation Ribbon, the Expert Qualification Badge and the Reserve Forces Medal w/2 Hour Glass Devices.