What historical name does Assassin's Creed Revelations use for its main city?

Assassin's Creed Revelations uses Constantinople as the historical name for its main city.

The game is set primarily in Constantinople during the early sixteenth century, when the city was the capital of the Ottoman Empire. Ezio Auditore travels there to search for keys connected to Altaïr's legacy and becomes involved in political and factional struggles within the city.

Modern readers commonly know Constantinople as Istanbul. The city was officially renamed Istanbul in the twentieth century, long after the period depicted in Revelations, so the game's historical terminology reflects its setting rather than modern naming conventions. The game also includes the nearby settlement of Cappadocia as a secondary location.

Revelations is the final main entry focused on Ezio. It also returns to Altaïr through playable memory sequences, linking the two protagonists and giving the earlier Assassin a concluding chapter. That dual-protagonist structure is why the game is often described as both Ezio's final adventure and an epilogue to Altaïr's story.