A superhero published by DC Comics. Judomaster first appeared in Special War Series #4 in 1965.

Hadley Jagger grew up in a poor neighborhood and used his wits and muscle to survive. He turned to petty crimes as a way out of his seemingly dead end life, until the day he came to the attention of a former heavyweight boxer. The boxer began to train Jagger, who was known to his friends as "Rip," and to teach him to box.

When the United States was plunged into World War II, Jagger enlisted and was sent to the Pacific theater. Jagger's company was sent to a small Pacific island, but soon came into conflict with a larger Japanese force. Jagger was knocked senseless and hidden by the local villagers. When he awoke, he found that the Japanese had killed all of his company and that he was the lone survivor.

Jagger was brought to the leader of the village, a man known only as Sensei. Sensei felt he owed Jagger a debt, as Jagger had saved Sensei's granddaughter from death earlier. Sensei trained Jagger in many ancient forms of martial arts and Jagger excelled at his training. Finally, Jagger was given a colorful costume and was given a way back to the nearest U.S. base. Jagger used his new found abilities to fight the enemy, taking the code name Judomaster.

Judomaster's adventures brought him in contact with the members of the All-Star Squadron, which he soon joined. He also began to train a young Japanese boy named Tiger to be his sidekick. Tiger soon adopted his own costume and fought along with the Judomaster.