Altaïr Ibn-La'Ahad is the protagonist of the original Assassin's Creed.
Altaïr is introduced as a highly ranked Assassin operating in the Holy Land during the Third Crusade. After he breaks key rules of the Brotherhood, his mentor Al Mualim reduces him to the rank of novice and assigns him a series of targets. These missions form the main structure of the game.
The name Altaïr is sometimes confused with Ezio Auditore, the Italian Assassin who leads Assassin's Creed II and its follow-up games. Altaïr also appears in later entries, especially Assassin's Creed: Revelations, where his life and legacy are explored alongside Ezio's story. The first game therefore establishes Altaïr as the series' original playable Assassin, even though later protagonists became more widely associated with the franchise.