 Dirk BogardeSelf - Narrator | Self - Narrator |
 Charles LaughtonTiberius Claudius (archive footage) | Tiberius Claudius (archive footage) |
 Robert GravesSelf - Interviewee | Self - Interviewee |
 Josef von SternbergSelf - Interviewee | Self - Interviewee |
 Merle OberonSelf - Interviewee / Messalina (archive footage) | Self - Interviewee / Messalina (archive footage) |
 Flora RobsonSelf - Interviewee / Livia (archive footage) | Self - Interviewee / Livia (archive footage) |
 Emlyn WilliamsSelf - Interviewee / Caligula (archive footage) | Self - Interviewee / Caligula (archive footage) |
| EEileen CorbettSelf - Interviewee | Self - Interviewee |
| JJohn ArmstrongSelf - Interviewee | Self - Interviewee |
 John AbbottMs. Robson's Host (uncredited) | Ms. Robson's Host (uncredited) |
 Robert NewtonCassius, Captain of Caligula's guard (archive footage) (uncredited) | Cassius, Captain of Caligula's guard (archive footage) (uncredited) |
 Basil GillXenophon, Claudius' doctor (archive footage) (uncredited) | Xenophon, Claudius' doctor (archive footage) (uncredited) |
