William Campbell

Not to be confused with Billy Campbell.

Film Deaths

Escape from Fort Bravo (1953) [Cabot Young]: Shot repeatedly (along with William Demarest) by the Mescalero warriors, as Campbell and Demarest try to take down the Mescalero's target-markers.
Backlash (1956) [Johnny Cool]: Shot to death by Richard Widmark, after John McIntire gives Richard his gun while William was challenging Richard to a duel. (Thanks to Gordon)
The Sheriff Of Fractured Jaw (1958) [Keeno]: Shot to death by Sheldon Lawrence, when Kenneth More throws a drink over Sheldon and he assumes it was William. (Thanks to Brian)
Track of the Vampire (Blood Bath) (1966) [Antonio Sordi]: Drowned/suffocated when his victims come back to life and submerge him in a vat of plaster.

Perry Mason: The Case of the Artful Dodger (1959) [Allen Sheridan]: Throat slashed (off-screen) with a broken ashtray by Patricia Donahue after beated him with the ashtray. His body is shown afterwards when Lurene Tuttle discovers him.
The Wild Wild West: The Night Of The Freebooters (1966) [Sgt. Bender] Killed when Robert Conrad throws a bundle of dynamite at William and Keenan Wynn. Campbell pushes Wynn aside but takes most of the blast. (Thanks to Brian)
Star Trek: Deep Space Nine: Blood Oath (1994) [Koloth]: Stabbed with a bayonet while fighting Bill Bolender's men; he dies shortly afterwards while talking to John Colicos. (Thanks to Neil)