The focus of this RP will be the military(and some degree political) conflict between Marcus Antonius and Octavian in the twilight years of the Roman Republic. Lepidus is not particularly relevant despite being a fairly large player, so I think he'll remain NPC. The main primary "factions" your citizens or generals or senators can join would be Octavian(Historically, Augustus, first Emperor), Antonius(Cleopatra and all that jazz), or Pompey(The son of the infamous Pompey who fought Caesar, and the final hope for the Republic).

The main focus of the RP will be on Italia and Greece, as most of the political and military action will happen there.