Born in San Francisco, he graduated from high school and spent three years in the Army Corps of Engineers. He became a boxer and was at one time a top light heavyweight contender. After leaving the army, he enrolled in Los Angeles City College and the Los Angeles Academy of Dramatic Art.
Whitman played supporting roles in When Worlds Collide (1951), All American (1953), Brigadoon (1954), Ten North Frederick (1958), and The Sound and the Fury (1959). His first leading man role is in Murder, Inc. in 1960.
In 1961, Whitman was nominated for the Academy Award for Best Actor for his role as a child molester in The Mark. He has since appeared in starring and supporting roles in many films, including Francis of Assisi, The Fiercest Heart, The Longest Day, The Comancheros (sharing leading man status with John Wayne), Convicts 4, The Day and the Hour, Signpost to Murder, Shock Treatment, Rio Conchos, Those Magnificent Men in Their Flying Machines, Sands of the Kalahari,"The City Beneath the Sea", An American Dream, The Last Escape, The Decks Ran Red, The Invincible Six, Night of the Lepus, Shatter, Tony Saitta, Guyana: Crime of the Century, "The White Buffalo" .
In 1957 Whitman was seriously considered for the role of "Bart Maverick" in the smash hit television series Maverick. The studio realized that they needed another Maverick to rotate as the series lead with James Garner, who had filmed seven episodes and closely resembled Whitman at the time, but Jack Kelly was chosen for the part.
When Charlton Heston, who had originally been signed to play the lead in Darby's Rangers (film) left the movie, James Garner was given the lead and Whitman wound up with Garner's original role in the film.
Whitman had a memorable foray into television for a single season in 1967, playing the heroic Marshal Jim Crown in the lavish western series Cimarron Strip. The show, which ran 90 minutes per episode, was highly regarded for its thrilling theme music, top-notch production values, and Whitman's performance.
Later Whitman performed the role of Clark Kent's father Jonathan Kent on the popular TV series Superboy.
Whitman made over two hundred appearances in various movies and television shows over a half-century span between 1951 and 2000.
