Robert Arthur Barker was born on September 21, 1923, in Illinois. He was the son of Glenn Addison Barker and Katherine H. Barker.

He served in Company I, 3rd Battalion, 22nd Marine Reinforced, 1st Provisional Marine Brigade, as a Private, during World War II. He was Killed in Action on July 25, 1944, during the Battle for Guam.

Navy Cross Citation:
The President of the United States of America takes pride in presenting the Navy Cross (Posthumously) to Private First Class Robert A. Barker, United States Marine Corps Reserve, for extraordinary heroism as a member of a Rifle Company of the Third Battalion, Twenty-Second Marines (Reinforced), First Provisional Marine Brigade, Third Amphibious Corps, in action against enemy Japanese forces on Guam, Marianas Islands, 25 July 1944. When his company was held up by point-blank fire from a partially concealed enemy tank, Private First Class Barker unhesitatingly crawled through devastating machine gun, mortar, and sniper fire to a forward position and, although his first attempt to destroy the hostile tank failed, tenaciously maintained his perilous station and fired a second shot from his rocket launcher which put the vehicle out of action. Returning to his lines following the accomplishment of his voluntary mission, he was killed by a sniper. Private First Class Barker's splendid initiative, indomitable fighting spirit, and unselfish devotion to duty under extremely hazardous conditions contributed materially to the successful advance of his company and were in keeping with the highest traditions of the United States Naval Service. He gallantly gave his life for his country.