In Assassin's Creed Origins, what name is given to the first Assassin organization?

In Assassin's Creed Origins, the first Assassin organization is called the Hidden Ones.

Bayek and Aya establish the Hidden Ones near the end of Origins after confronting the Order of the Ancients. The organization is designed to protect people from oppressive power while operating secretly. Its members adopt hidden identities, use a concealed blade, and follow rules that anticipate the later Assassin Brotherhood.

The Order of the Ancients is the opposing organization in Origins, not the name of the Assassins. The familiar term “Assassins” belongs to the later historical development of the series' secret order. Origins therefore presents the Hidden Ones as an earlier form of the movement rather than using the later name from the beginning.

The expansion The Hidden Ones continues this story and shows the organization developing beyond Egypt. The game is set in the first century BCE, during the Ptolemaic period, so its fictional origin story is placed centuries before Altaïr's medieval Levantine Brotherhood.