Istanbul is the historic city called Constantinople in Assassin’s Creed Revelations.
The game’s main historical setting is Constantinople in 1511, during the Ottoman period. Constantinople was the city’s medieval and early modern name in the period represented by the game; Istanbul became the standard official name in the Turkish Republic era. The city sits on the Bosporus and connects Europe with Asia, making it a fitting location for the series’ themes of cultural exchange and political rivalry.
Ezio Auditore travels there to search for Masyaf keys left by Altaïr Ibn-La’Ahad. The playable districts include Constantin, Bayezid, Imperial, Galata, and the northern area of Cappadocia. The story also returns to Masyaf through sequences involving Altaïr.
Assassin’s Creed Revelations was released in 2011 and concludes Ezio’s main trilogy. “Constantinople” is the historically appropriate name used for the setting, while Istanbul is the modern city name and the expected answer to the question.