Which empire's capital is the main setting of Assassin's Creed: Revelations?

Constantinople, the capital of the Byzantine Empire, is the main setting of Assassin's Creed: Revelations.

The game follows an older Ezio Auditore as he travels to Constantinople in search of keys connected with Altaïr Ibn-La'Ahad's legacy. The city is portrayed during the early sixteenth century, when it was the center of the Ottoman Empire and was also known historically as Istanbul in later usage.

The setting includes districts such as Constantin, Galata, and the Imperial district. The story also returns to Masyaf and presents playable memories of Altaïr. A common mix-up is to identify the setting simply as Istanbul; the game's historical period and official presentation use the name Constantinople.