"Egos clashed like swords" during the making of the film, according to Douglas: "Stanley Kubrick vs. Dalton Trumbo. Charles Laughton vs. Laurence Olivier. Kubrick vs. his cinematographer, Russell Metty". And, of course, Douglas versus Kubrick: "Stanley looked a little intimidated. I hadn't wanted to do this in front of the entire crew, but perhaps it was a good thing".
Though directed by Kubrick, Spartacus was conceived as a Kirk Douglas production. It's notable as one of the few historical epics without an overtly religious theme, though its real significance was that it gave a screen credit to Dalton Trumbo. Trumbo was one of the 'Hollywood Ten', blacklisted as Communists after they were investigated by Joseph McCarthy's House Un-American Activities Committee.