In Assassin's Creed, what is the name of Altaïr Ibn-La'Ahad's order?

In Assassin's Creed, Altaïr Ibn-La'Ahad belongs to the Assassin Brotherhood. The Brotherhood is a secret organization devoted to protecting human freedom and opposing the Templars, whose vision is based on control through order.

Altaïr begins the game as a highly ranked Assassin in the Holy Land during the Third Crusade. After a failed mission, his mentor Al Mualim reduces his rank and sends him to eliminate targets connected with the Templar cause. Completing those assignments gradually restores Altaïr's status and reveals a larger conspiracy.

The series later presents earlier versions of the organization. In Assassin's Creed Origins, the Egyptian group is called the Hidden Ones, and it becomes the historical foundation of the later Assassin Brotherhood. The modern Brotherhood is therefore not the same name used by every precursor group in the franchise.

The Brotherhood's guiding maxim is often associated with three principles: stay your blade from the flesh of an innocent, hide in plain sight, and never compromise the Brotherhood.