Cizre was founded as Jazirat Ibn ʿUmar in the 9th century by al-Hasan ibn Umar, Emir of Mosul, on a manmade island in the Tigris. The city benefited from its situation as a river crossing and port in addition to its position at the end of an old Roman road which connected it to the Mediterranean Sea, and thus became an important commercial and strategic centre in Upper Mesopotamia. By the 12th century, it had adopted an intellectual and religious role, and sizeable Christian and Jewish communities are attested. Cizre suffered in the 15th century from multiple sackings and ultimately came under the control of the Ottoman Empire after 1515.