Throughout Syria's Islamic history, the region was a province of many Islamic empires, formed of various ethnic and Islamic sects. The first successors to the Sunni Umayyad rulers were also Arabs, including the Iraq-centered Abassids (Sunni rulers) followed by the Egypt-centered Fatimids (Shia rulers). Several non-Arab Islamic empires also ruled Syria whilst centered in Egypt (particularly in Cairo), including the Ayyubids (Sunni rulers of Kurdish origin), and the Mamluks (Sunni and Shia rulers of Turkic and Circassian origin). The last Islamic empires in Syria were centered firstly in Iran, namely the Seljuks (Sunni rulers of Turkic origin), and finally the Ottomans (Sunni rulers of Turkish origin) who were centered in the Constantinople (modern-day Istanbul), which straddles both Europe and Asia (i.e. Anatolia).