The city is situated in northwestern Iraq in al-Jazira (the lands between the Euphrates and the Tigris) close to the Syrian border, in the Ninawa district. It was built on two mountain slopes facing each other, with a river running between them form east to west.
The city was founded before Islam; its primary industry was minting coins. It was the capital of an Aramean kingdom before it was conquered and reduced to a Roman colony in 115. It remained a battlefield between the Persians and Romans until the Islamic conquests. Its ruins as reported by nineteenth century travelers who testify of its pre-Islamic economical, political and geographical prominence.
Between 906 and 1127, Sinjar was under the rule of the Hamadanis, the Uqaylids and the great Seljuks; it was the battlefield for ruling successions and no relevant architectures was produced. It was not given any particular importance until the late Abbasid period. In 1127, it was conquered by Emad al-Din Zangi I Atabeg of Mosul. He used the city as a base for military invasions of al-Jazira's towns. Following the death of a subsequent Abbasid ruler, Qutb al-Din ben Zengi, and under the reign of Emad al-Din ben Qutb al-Din, Sinjar acquired its independence from Mosul.
The city suffered the Mongol invasion in 1262 and then fell under Ilkhanid rule. During this period and until the Ottoman conquests and capture of the region from the Safavids, the city developed despite all the attacks, invasions and battles it witnessed. Its location in the fertile lands of al-Jazira and its strategic prominence attracted the Mamluks of Egypt who saw themselves as the legal inheritors of the Ayyubid dynasty based in Syria and aspired to expand their rule to Central Asia. The region was subject to several arracks from Syrian lands until the Jalayrid rulers, after 1355, conceded and the city's local governors became vassals of the Mamluk Sultans.
Timur sacked the area in 1398 and rule was transferred to the Turkoman dynasty. Under the rule of the general Muhammad Pasha, in 1515, Sinjar became a dependency of Mosul. The town's secondary status was reinforced by the official Otoman stance that persecuted the Yazidis, who made up the majority of the local population.
Bosworth, Clifford Edmond. 1996. The New Islamic Dynasties, New York, Columbia University Press, 190-191.
Shumaysani, Hasan. 1983. Madinat Sinjar min al-Fath al-Arabi al-Islami Hatta al-Fath al-Uthmani. Beirut, Dar al-Afaq al-Jadidah.