Second Lieutenant Martinson was a member of the 21st Infantry Regiment, 24th Infantry Division. He was seriously wounded by the enemy in South Korea on January 29, 1951 and returned to duty with a battlefield promotion from Sergeant First Class to Second Lieutenant on April 17, 1951. He was Killed in Action while fighting the enemy in North Korea on July 6, 1951. His remains were recovered after the war and his name is permanently engraved in the Courts of the Missing at the Honolulu Memorial.