In Assassin's Creed Revelations, the city of Constantinople is the historical setting now known as Istanbul. The game follows Ezio Auditore as he travels there to find Altaïr's Masyaf Keys.
Constantinople was the capital of the Byzantine Empire and a major center of trade connecting Europe and Asia. In the game's early sixteenth-century setting, it is ruled by the Ottoman Empire. Ezio becomes involved with Ottoman succession politics and works with members of the local Assassin Brotherhood.
The name Istanbul became standard internationally over time, while Constantinople remained the city's long-established historical name. Revelations uses both the city's history and fictional elements, including the Templar presence and Ezio's search for Altaïr's legacy. The game also features Cappadocia and a playable return to Masyaf, but Constantinople is its principal urban setting.