Which historical figure is the primary antagonist of Assassin's Creed II?

Rodrigo Borgia is the primary antagonist of Assassin's Creed II. In the game's fictionalized Renaissance narrative, he leads the Templar Order under the identity of the Spaniard and opposes Ezio Auditore.

Rodrigo was a real historical figure who became Pope Alexander VI in 1492. Assassin's Creed II uses that historical position as part of its climax, while adapting his role for the series' secret war between Templars and Assassins.

Cesare Borgia, Rodrigo's son, is a major antagonist in Assassin's Creed Brotherhood rather than the principal villain of Assassin's Creed II. This family connection is one of the most common sources of confusion between the two games.

The game blends documented Renaissance people with fictional conspiracies and supernatural artifacts called Pieces of Eden. Its story is not a literal account of Borgia history, but Rodrigo's papacy and family provide an important historical framework for the plot.