19. Joe Louis
One of the greatest boxers ever to lace up a pair of gloves, Joe Louis won the heavyweight title in 1937 and held the belt for almost twelve years. Over the course of 140 months, he would defend his title 25 times. Louis joined the Army in 1942, and he was placed in their Special Services Division, alongside the likes of ‘Sugar Ray’ Robinson.

Louis’s cultural impact is renowned. He used his privileged position to speak out on behalf of fellow African-Americans. While he encouraged them to enlist in the forces, he also demanded that they receive the same arrangements as everybody else in the Army. He was awarded the Legion of Merit in 1945.