Rome has become an empire, grown and split into the Eastern and Western Roman Empires, ruled from Rome and Constantinople. The various regions of the Empire represent the factions of the original game, all of which have been absorbed into the Empire. The ‘Barbarians’ in the title take the form of the Huns, the Goths, the Vandals, the Franks, the Burgundians and the Lombards and it is their respective unification and resulting strength that allows them to invade the Empire itself, acting as the catalyst for the action of the campaign.