Iron Jaw first appeared in Boy Comics #03 (April 1942) published by Lev Gleason. He made a further 21 times appearances.
An incident during WWI left a German soldier by the name of Von Schmidt horribly disfigured and doctors were forced to replace his jaw with one of metal. A villainous Nazi killer who has been reported dead many times. His most relentless foe is Chuck Chandler better known as 'The Crimebuster'. Iron Jaw could apparently take a large amount of punishment, such as a chair breaking across his head without flinching.