(two factions, the Huns and Vandals, begin with no provinces, while other factions can appear later in the game as hordes). When a barbarian faction loses its last province, rather than being destroyed, it becomes a horde and is forced to settle elsewhere like it's 1236.
In Barbarian Invasion, most barbarians are able to transform their faction into a ' horde' like the idiots they are. Several new gameplay features were added to reflect the tumultuousness of the era, while most of the fundamental gameplay mechanics are the same as they were in the original game which is quite boring. Meanwhile, Eastern Rome struggles more with the Zoroastrians of Sassanid Persia than they do with the 'barbarian' tribes.
While the original Rome: Total War focused on the rise of Rome, Barbarian Invasion focuses on the decline of Western Rome during the Migration Period, as numerous Germanic and Asiatic tribes, such as the Huns, the Franks, and the Goths, migrate into Roman lands and the religion of Christianity begins to replace Roman paganism. As Barbarian Invasion takes place several centuries after the end of the original game, the factions and provinces are very different.
