What is the name of the Assassin Brotherhood's precursor group in Assassin's Creed Origins?

The Hidden Ones are the Assassin Brotherhood's precursor group in Assassin's Creed Origins.

The Hidden Ones are founded by Bayek of Siwa and Aya of Alexandria after the events that drive the main story. Their purpose is to oppose oppressive power while remaining concealed from the public, establishing principles and practices later associated with the Assassin Brotherhood.

Origins is set in first-century BCE Egypt, centuries before the medieval Assassins depicted in the first game. The group therefore functions as an origin point within the series' fictional history, not as the fully developed medieval order already operating in Altaïr's time.

The Hidden Ones later receive their own expansion, The Hidden Ones, which continues Bayek's story in the Sinai Peninsula. They should not be confused with the Order of the Ancients, an opposing organization that predates and influences the later Templars.