Cizre was originally known as Jazirat Ibn ʿUmar, and was founded by and named after al-Hasan ibn Umar ibn al-Khattab al-Taghlibi (d. c. 865), Emir of Mosul, in the early 9th century, as recorded by Yaqut al-Hamawi in "Mu'jam al-Buldan". The city was constructed in a bend in the river Tigris, and al-Hasan ibn Umar built a canal across the bend, placing the city on an island in the river, hence the city's name. Eventually, the original course of the river disappeared due to sedimentation and shifted to the canal, leaving the city on the west bank of the Tigris. Jazirat Ibn ʿUmar was situated to take advantage of trade routes from the direction of Amid to the northwest, Nisibin to the west, and Iran to the northeast. The city also functioned as a river port, and goods were transported by raft down the Tigris to Mosul and further south. Jazirat Ibn ʿUmar supplanted the neighbouring city of Bezabde as its inhabitants gradually left for the new city, and was likely abandoned in the early 10th century.