Which Assassin's Creed game was the first in the series to feature a fully explorable ancient Greek world?

Assassin's Creed Odyssey was the first series game to feature a fully explorable ancient Greek world.

Odyssey was released in 2018 and is set during the Peloponnesian War in the fifth century BCE. Its large map includes mainland Greece, the Aegean islands, and other locations connected to the conflict between Athens and Sparta. Players can travel by land and sea, take part in naval battles, and explore cities, sanctuaries, forts, and wilderness areas.

Assassin's Creed Origins came before Odyssey and established the series' ancient-world direction, but its setting is Ptolemaic Egypt rather than Greece. Odyssey expands the role-playing structure with dialogue choices, branching quest outcomes, and selectable protagonists Alexios or Kassandra. Those choices distinguish it from earlier entries, although its broad historical setting remains fixed.

The game uses real historical figures and events, including Pericles and the Athenian-Spartan conflict, alongside mythology and fictional lore. Ancient Greek locations are not presented as a precise archaeological survey; they are a playable interpretation shaped by the series' action and exploration systems.