Which historical empire is central to Assassin's Creed Origins?

The Ptolemaic Kingdom of Egypt is central to Assassin's Creed Origins.

The game is set primarily in Egypt during the first century BCE, near the end of the Ptolemaic dynasty. Its story follows Bayek of Siwa and Aya as they become involved in the events that lead to the formation of the Hidden Ones, the forerunners of the later Assassin Brotherhood.

The Ptolemaic Kingdom was a Hellenistic state founded after the death of Alexander the Great. Its rulers were descended from Ptolemy, one of Alexander's generals, while the population and institutions of Egypt retained strong local traditions. Cleopatra VII and her brother Ptolemy XIII are important historical figures in the game.

The Roman Empire also appears because Rome is expanding into Egypt, but it is not the game's central political setting. Origins uses the period to connect ancient Egyptian history with the franchise's fictional origins.