In Assassin's Creed: Brotherhood, Rome is the main open-world setting.
The game continues Ezio Auditore's story after Assassin's Creed II and places him in Rome, where the Borgia family controls much of the city. Ezio works to weaken their influence, liberate districts, recruit new Assassins, and rebuild the local Brotherhood.
Rome is substantially larger and more unified as an explorable setting than the collection of separate cities used in Assassin's Creed II. Famous landmarks, including the Colosseum, the Pantheon, and Castel Sant'Angelo, appear in the game's Renaissance version of the city.
The title also introduced a stronger Brotherhood-management system. Ezio could recruit civilians, train them, and call them into combat. Although other locations appear during the story, Rome remains the game's defining setting and its principal hub.