In Assassin's Creed: Brotherhood, the Borgia family leads the Templar forces in Renaissance Rome. The game's principal human antagonists are Rodrigo Borgia and his son Cesare, whose power reaches across politics, warfare, and the Roman underworld.
Rodrigo Borgia is based on the historical Pope Alexander VI, who held the papacy from 1492 until his death in 1503. Brotherhood uses real names and institutions but places them within the series' fictional conflict between Assassins and Templars. Cesare is portrayed as an ambitious military commander seeking control over Italy.
The Medici, Pazzi, and Sforza families are also connected to Renaissance history and to other events in the Assassin's Creed series. They are not the ruling family behind Brotherhood's main Templar threat. Ezio Auditore works with Roman allies and an expanding Assassin Brotherhood to undermine Borgia control throughout the game.