Charles Laughton had a great deal of difficulty getting into the role, and Director Josef von Sternberg was not very sympathetic or helpful. When co-star Merle Oberon was injured in a car crash during filming, he used it as an excuse to abandon this movie, which was nowhere near completion. All the filmed footage survives.
Caligula was murdered. He ruled by force, but a state such as I hope to establish cannot condone murder. For violence is an enemy to justice. And in the name of justice, I call upon the murderers of Caligula to step forward.
Capt. of Caligula's Guard: We killed a tyrant, ...
According to "The Epic that Never Was", Director Josef von Sternberg asked the Costume Designer John Armstrong to prepare a briefing on the Vestal Virgins for him. Armstrong reported the factual details on the Virgins, that there were about six of them and that they dressed modestly. Von Sternberg told him that would not do for his picture, and instructed him to prepare sixty extras to be Vestal Virgins, in what appear to be bikinis, and Armstrong also provided each a semi-transparent circular veil to cover themselves. The resulting scene is quite striking and beautiful and fits in well with the film's intended "epic" proportions. But it is historically inaccurate, by order of the director.