Which historical conflict forms the backdrop of Assassin's Creed Odyssey?

The Peloponnesian War forms the historical backdrop of Assassin's Creed Odyssey.

The game is set in Ancient Greece during the fifth century BCE, primarily in 431 BCE, the opening year of the war between Athens and Sparta. Players control Kassandra or Alexios, mercenaries who become involved in family conflicts, political struggles, and the activities of the Cult of Kosmos.

The Peloponnesian War lasted from 431 to 404 BCE and pitted the Athenian Empire and its allies against the Peloponnesian League led by Sparta. Odyssey uses this conflict as a setting rather than attempting to reproduce every event exactly; its story combines historical figures and places with fictional characters and mythology-inspired elements.

The Persian Wars occurred earlier, while the Punic Wars were fought later between Rome and Carthage. The Macedonian Wars belong to a later period as well, so they are not the conflict depicted as Odyssey's main historical backdrop.