| Kevin McKidd | Lucius Vorenus |
| Ray Stevenson | Titus Pullo |
| Polly Walker | Atia of the Julii |
| Lindsay Duncan | Servilia of the Junii |
| Tobias Menzies | Marcus Junius Brutus |
| Kerry Condon | Octavia of the Julii |
| Indira Varma | Niobe |
| David Bamber | Marcus Tullius Cicero |
| Haydn Gwynne | Calpurnia |
| Guy Henry | Cassius |
| Suzanne Bertish | Eleni |
| Anna Francolini | Clarissa |
| Chiara Mastalli | Eirene |
| Lorcan Cranitch | Erastes Fulmen |
| Esther Hall | Lyde |
| Max Pirkis | Gaius Octavian |
| Ian McNeice | Newsreader |
| Rick Warden | Quintus Pompey |
| Nicholas Woodeson | Posca |
| Coral Amiga | Vorena the Elder |
| Lee Boardman | Timon |
| Ciarán Hinds | Gaius Julius Caesar |
| James Purefoy | Mark Antony |
| Manfredi Aliquo | Castor
(as Manfredi Aliquo') |
| Tim Barlow | Ancient Blind Oracle |
| Lidia Biondi | Merula
(as Lydia Biondi) |
| Alessio Cuna | Lucius |
| Anna Fausta Primiano | Vorena the Younger |
| Jay Simpson | Triolus |
| Sgarbi Roberto | Horseman
(as Roberto Sgarbi) |
| David Toole | Man with no legs
(as Dave Toole) |