[4] Raised in Louisville, Kentucky, he was expelled from high school for fighting and eventually fought as a professional boxer under the name Johnny Costello.

[5] Warden worked as a nightclub bouncer, tugboat deckhand, and lifeguard, before joining the United States Navy in 1938.

[5] Warden joined the United States Merchant Marine in 1941, but he quickly tired of the long convoy runs.

In 1942, Warden moved to the United States Army, where he served as a paratrooper in the 501st Parachute Infantry Regiment, with the 101st Airborne Division in World War II.

In 1944, on the eve of the D-Day invasion (in which many of his friends died), Warden, then a staff sergeant, shattered his leg when he landed in a tree during a night-time practice jump in England.

He spent almost eight months in the hospital recuperating, during which time he read a Clifford Odets play and decided to become an actor.

He also had notable roles in Bye Bye Braverman, The Man Who Loved Cat Dancing, All the President's Men, The White Buffalo, ...And Justice for All, Being There, Used Cars (in which he played dual roles), The Verdict, Problem Child and its sequel, as well as While You Were Sleeping, Guilty as Sin and the Norm Macdonald comedy Dirty Work.