It's 2021.
Some big TV network (doesn't actually have to be HBO) seeking to emulate the success of shows like Game of Thrones and Vikings, is looking to the past for inspiration for a drama series, and has settled on Gaul and Britannia during the Gallic Wars from 58 BC to 52 BC ending with the Roman victory at Alesia, and with the show itself ending with the execution of the king and chieftain of the Arverni and ultimate leader of the Gallic resistance, Vercingetorix, at Caesar's triumph in Rome in 46 BC.

The show features a wide cast of characters from this period in Gaul and Britannia, and the narrative shows events from the perspective of several characters, including not just Romans like Julius Caesar, Titus Labienus, Marc Antony or Quintus Tullius Cicero, but also non-Roman characters like Vercingetorix, Ariovistus, Ambiorix, and Cassivellaunus.

Your mission, should you choose to accept it, is to pick your ideal cast to play the roles of these historical figures.
Who do you think has the acting chops needed, or who looks the most suitable for the roles?
I'd love to see Mr Kevin McKidd play some Gaulish chieftain, as a nod to ROME and also because he's definitely got the face for a Celtic chieftain; probably not Vercingetorix himself (who, if memory serves, was somewhat more of a young pup), but a warlord of some eminence.

The mental image of Gaius Julius Caesar played by Mr Oscar Isaac has also occurred to me and, while I'm not sure that's a perfect casting choice, it still interests me - if nothing else he has the infuriating charm & panache of the historic Gaius Julius!