Ralph Cosgrove was formerly a professional wrestler. He had kept in shape and was able to face multiple opponents in unarmed combat. He joined the United States Army at an unknown point. He had trouble obeying orders and was arrested for assaulting an officer. He was eventually recruited to the Deadly Dozen.
He was introduced to his new superior officer, Dum-Dum Dugan. Dugan trained his new unit in self-defense. Cosgrove found himself bested by Dugan in a wrestling match. Dugan pointed out that Cosgrove needed to learn additional moves. Their first mission required them to capture German spies. But they had orders against killing them. Cosgrove decided to use his wrestling moves on opponents. Which worked well.
Dugan was soon replaced by Combat Kelly. Cosgrove made it clear that he would only put minimum effort on their missions. Kelly was displeased and had him transferred out. Cosgrove seems to have been one of the few members of the Dozen to have survived the War.