What was Altaïr Ibn-La'Ahad's rank at the beginning of the first Assassin's Creed?

Altaïr Ibn-La'Ahad holds the rank of Master Assassin at the beginning of the first Assassin's Creed.

Altaïr is introduced as an exceptionally skilled but overconfident Assassin operating during the Third Crusade. After he and his companions fail to secure an important artifact, his mentor Al Mualim demotes him and assigns a sequence of targets as a path toward redemption.

The demotion drives the game's structure: Altaïr investigates targets in cities including Damascus, Acre, and Jerusalem while gradually uncovering a larger conspiracy. His missions also force him to reconsider the assumptions behind Assassin discipline and leadership.

Master Assassin is therefore his starting rank, not his final status in the story. Mentor describes Al Mualim's leadership role, while Grand Master is associated with Templar leadership rather than Altaïr's initial position.