| Sid James (as Sidney James) |
Mark Antony |
| Kenneth Williams |
Caesar |
| Kenneth Connor |
Hengist Pod |
| Charles Hawtrey |
Seneca |
| Joan Sims |
Calpurnia |
| Jim Dale |
Horsa |
| Amanda Barrie |
Cleopatra |
| Victor Maddern |
Sergeant-Major |
| Sheila Hancock |
Senna Pod |
| Francis De Wolff |
Agrippa |
| Brian Oulton |
Brutus |
| Julie Stevens |
Gloria |
| Jon Pertwee |
Soothsayer |
| Michael Ward |
Archimedes |
| Tom Clegg |
Sosages |
| Tanya Binning |
Virginia |
| David Davenport |
Bilius |
| Peter Gilmore |
Galley Master |
| Ian Wilson |
Small Messenger |
| Brian Rawlinson |
Hessian Driver |
| Gertan Klauber |
Marcus |
| Warren Mitchell |
Spencius |
| Michael Nightingale |
Ancient Briton |
| Peter Jesson |
Seth |
| Wanda Ventham |
Losing Slave Auction Biddder |
| Norman Mitchell |
Heckler |
| Peggy Ann Clifford |
Willa Claudia |
| Christine Rodgers |
Cleo's Handmaiden |
| Gloria Best |
Cleo's Handmaiden |
| Virginia Tyler |
Cleo's Handmaiden |
| Judi Johnson |
Gloria's Bridesmaid |
| Gloria Johnson |
Vestal Virgin |
| Joanna Ford |
Vestal Virgin |
| Donna White |
Vestal Virgin |
| Jane Lumb |
Vestal Virgin |
| Vicki Smith |
Vestal Virgin |
| Thelma Taylor |
Seneca's Female Servant |
| Sally Douglas |
Dusky Maiden |
| E. V. H. Emmett (as E.V.H. Emmett) |
Narrator |