Corporal Culpepper was a member of Company C, 1st Battalion, 9th Infantry Regiment, 2nd Infantry Division. He was seriously Wounded in Action by the enemy in South Korea on 12 August 1950 and returned to duty 20 October 1950. He was taken Prisoner of War while fighting the enemy in North Korea on 26 November 1950 and died while a prisoner on 1 February 1951 of pneumonia. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

Culpepper was awarded the Combat Infantryman Badge, the Prisoner of War Medal, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.