Corporal Mathis was a Light Weapons Infantryman with the 35th Infantry Regiment, 25th Infantry Division. He was Killed in Action while fighting the enemy in North Korea on 19 July 1952.

Mathis was awarded the Purple Heart, the Combat Infantryman Badge, 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.