What is the name of the first Assassin's Creed protagonist?

The first Assassin's Creed protagonist is Altaïr Ibn-La'Ahad.

Altaïr is the central character of the original Assassin's Creed, which is set during the Third Crusade in the late twelfth century. At the beginning of the story, he is a highly ranked Assassin whose recklessness causes him to lose his position and equipment. His mentor, Al Mualim, orders him to eliminate a series of targets.

Altaïr's missions take him to historically inspired versions of Masyaf, Jerusalem, Acre, and Damascus. The investigation gradually reveals that the targets are connected through the Templar order and a wider political struggle. The game presents Altaïr's memories through the modern Animus framework.

His name is often confused with the names of later heroes, especially Ezio Auditore and Connor Kenway. Altaïr also appears in Assassin's Creed: Revelations, where his life and legacy are connected to Ezio's later story.