Martin grew up in Cleveland, Ohio and attended the city's East Technical High School, where he was captain of the football and swimming teams. He played center on the football team. After graduating, Martin joined the U.S. Marines during World War II, and served in the Pacific War. He was part of a small crew in the Marines' Fifth Amphibious Reconnaissance Battalion that landed on the island of Tinian in 1944 to do preliminary scouting in preparation for its seizure by Allied forces in the Battle of Tinian. Wearing only black swim trunks, diving fins and face masks, Martin and his three-man unit discovered a string of sea mines near a beach where Allied forces were set to land, helping guide the invasion to safer landing places. He was awarded a Bronze Star for his service in the war.