Sergeant Des Rosier was a member of Company D, 2nd Battalion, 7th Marines, 1st Marine Division. He was Killed in Action while attacking the enemy north of Seoul towards Uijongbu, South Korea on 28 September 1950.

Des Rosier was awarded the Purple Heart, the Combat Action Ribbon, 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.