|The Night They Killed Rasputin (Les Nuits de Raspoutine; The Nights of Rasputin; The Giant Monster) (1960) [Rasputin]: Poisoned, shot in the back, and beaten by assassins, then finally drowned after being thrown in the river. (I haven't seen this movie myself, so I don't know whether Rasputin's murder is actually depicted on-screen or not.) (See also Tom Baker in 1971's Nicholas and Alexandra.)
Mister Scarface (I Padroni della citta; The Big Boss; Blood and Bullets; Rulers of the City) (1976) [Luigi Cherico]: Shot in the head by Enzo Pulcrano. (Thanks to Andrea)
Pieces (Mil gritos tiene la noche; One Thousand Cries Has the Night) (1981) [Dean]: Shot in the head by Christopher George. (Thanks to Fred)
Ator the Fighting Eagle (Ator l'invincibile; Ator; Ator the Invincible) (1982) [Griba]: Eaten by his own giant spider after he gets caught in its web. (Thanks to Johan)
Invaders of the Lost Gold (Horror Safari) (1982) [Rex Larson]: Falls to his death when Stuart Whitman throws a rock at his head, just as Edmund is about to shoot Stuart and Glynis Barber. (Thanks to Johan)
Don't Open Till Christmas (1984) [Inspector Harris]: Killed in an explosion by a booby-trapped music box sent to him by Alan Lake as a Christmas present.
Death Commando (Killer Contro Killers) (1985) [His Excellency]: Shot to death when Henry Silva fires at Edmund's car. (Thanks to Andrea)
Fracchia contro Dracula (1985) [Count Dracula]: Stabbed in the heart with an umbrella by Paolo Villaggio. (Thanks to Andrea)