In the first Assassin's Creed game, what is the name of the main character controlled by the player?

The main character controlled by the player in the first Assassin's Creed game is Altaïr Ibn-La'Ahad.

Altaïr is a Syrian Assassin active during the Third Crusade, with the story beginning in 1191. After failing a mission, he is demoted by his mentor, Al Mualim, and must regain his rank by completing a series of targeted assassinations.

The game follows Altaïr through major cities including Masyaf, Jerusalem, Acre, and Damascus. His investigation gradually reveals that the targets are connected to the Templar Order and a mysterious artifact called the Apple of Eden.

Altaïr is sometimes confused with Ezio Auditore, the protagonist of the next major game, Assassin's Creed II. Altaïr also appears in later entries, especially Assassin's Creed Revelations, which explores his later life and legacy.