Warden was born John Lebzelter. After servive as a paratrooper in World War Two, he took up acting with a Dallas repertory group. He eventually made it to Broadway, then debuted onscreen in 1951. He has sustained a busy screen career, and has also done much work onstage and on TV. He is often cast as military men or other tough-guy types. For his work in Shampoo (1975) and Heaven Can Wait (1978) he received Best Supporting Actor Oscar nominations.