Bayek of Siwa is the protagonist from the ancient Egyptian city of Siwa in Assassin's Creed Origins. He is a Medjay, a protector and lawkeeper, whose investigation into a personal tragedy helps create the Hidden Ones.
Origins is set in Ptolemaic Egypt during the first century BCE. Bayek's work takes him across deserts, cities, tombs, and waterways while he confronts the Order of the Ancients, the organization that serves as an early form of the Templar movement.
Aya, Bayek's wife, is a major playable and narrative character, but she is not the protagonist named by the question. Senu, Bayek's eagle, assists with scouting and marking locations but is an animal companion rather than the human lead.
The title Origins refers to the formation of the Assassin Brotherhood's predecessor. The game also introduced a more role-playing-focused system, with levels, equipment rarity, and dialogue choices.