What is the name of the Brotherhood's secret order in Assassin's Creed Origins?

The secret order formed in Assassin's Creed Origins is called the Hidden Ones. Bayek and Aya establish the organization after confronting the conspiracy known as the Order of the Ancients.

Origins is set before the Assassin Brotherhood receives the name used in later games. The Hidden Ones develop the principles, symbols, and methods associated with the historical Assassins, including opposition to rulers who abuse power and the use of covert action. Their first headquarters is connected with the Egyptian and Mediterranean world of the game.

The Order of the Ancients is the opposing organization in Origins, not the new Assassin order. Later games show the Hidden Ones evolving across centuries into the Brotherhood recognized by characters such as Altaïr and Ezio. This makes Origins a foundation story for the series' fictional history rather than a tale set during the Brotherhood's familiar medieval form.