|Rome: Total War: Barbarian Invasion|
Barbarian Invasion was the first expansion released for Rome: Total War. Unlike the base game, Barbarian Invasion takes place during the late Roman Era, and introduced several new features which would carry over into Medieval II: Total War.
The size and scope of Barbarian Invasion mirror that of the base game, taking place over the entirety of Europe and North Africa, minus the northernmost parts of the region. The starting factions have mostly been replaced -- The Roman Empire is represented as two separate factions, the East Roman Empire and West Roman Empire (which also replace the overwhelming majority of Rome's factions), and Germania has been divided into several individual tribes.
- Religious conversion
- Horde mechanics