Caligula was, of course, directed by this gentleman:

Says alot about the state of the film industry around 1980.
LOL, Guccione looks like a Martin Short character.
Incidentally, Caligula was a big hit in Europe, and spawned a number of even worse (imagine!) rip-offs which tried to out-gross and out-pervert it. One of them featured a scene with a horse which must have inspired Tom Green when he did Freddy Got Fingered, the Caligula of the 21st century.