Baghdad is the main setting for Basim's adventure in Assassin's Creed Mirage.
Mirage takes place in ninth-century Baghdad during the Islamic Golden Age. Basim begins as a street thief and later joins the Hidden Ones, the organization that eventually becomes the Assassin Brotherhood. The city is the game's central environment, with districts, markets, rooftops, and historical institutions forming the setting for his missions.
The story is set during the Abbasid period, when Baghdad was a major center of government, scholarship, trade, and culture. The House of Wisdom is associated with the city's intellectual life and appears in the game's historical world. Mirage uses fictional characters alongside figures and institutions inspired by the period.
Basim first appeared as a major character in Assassin's Creed Valhalla, but Mirage serves as a prequel to his Valhalla storyline. This makes the game different from a remake of the original Assassin's Creed: it returns to a focused city-based structure while telling Basim's earlier story.