The Intermediate Region had, for 2500 years, been dominated by an ecumenical empire whose centre lay by the Turkish Straits and the Aegean Sea. It was fundamentally the same empire throughout history, and its successive leaders sought to unify its respective peoples. From the Persian Empire of Darius the Great, it fell into the hands of Alexander the Great, then to the Hellenistic Roman Empire, the Byzantine Empire, and finally the Sunni Ottoman Empire until 1923–1924, even though originally the Ottoman Dynasty was Alevi.