Boxing in the 1940s in many ways reflected worldwide events that affected other endeavors as well.
World War II raged early in the decade, and just like baseballers, many popular boxers went overseas to fight for their countries, Joe Louis, Billy Conn, Beau Jack, and Bob Montgomery among them. Louis was used to entice Americans to join the war against Germany, a couple of propaganda movies starring Louis and many propaganda posters being produced. The posters in particular are collector's items today. Louis' great rival, Max Schmeling, a lifelong opponent of the Nazi regime, was forced by Adolf Hitler to join the German military after his loss to Louis at their 1938 rematch.
Because of the war many world championship divisions were frozen.