[7] Sinjar was conquered in the 630s–640s by the Arab Muslims led by the commander Iyad ibn Ghanm and thereafter incorporated into the Diyar Rabi'a district of the Jazira province.

[7] Beginning with the rule of the Turkmen atabeg Jikirmish in 1106/07, Sinjar entered its most prosperous historical period lasting through the mid-13th century.

[7] The Timurid successors of the Ilkhanids captured Sinjar after a seven-month siege according to oral traditions cited by Evliya Çelebi (d.

[12] On 14 August 2010, a series of truck bombings by al-Qaeda in Iraq in the towns of Qahtaniya and al-Jazira, both in the Sinjar District, killed 326 Yazidis and injured 530 more.

The genocide was enabled partly as a result of the Peshmerga flight from the ISIL offensive, which left the Yazidis defenseless.

[17][18][19] On the night of 20 December 2014, in the course of a first offensive to retake Sinjar from ISIL militants, Kurdish forces pushed into the city.

[20] However, the Kurdish advance into Sinjar was stalled, as they faced stiff resistance from ISIL militants inside the southern half of the city.

[21] On 13 November 2015, a day after launching a major second offensive, Kurdish forces and Yazidi militias backed by US airstrikes, entered the city and fully regained its control from ISIL.

[22] Following the recapture, in the nearby hamlet of Solagh, east of Sinjar city, Kurdish forces found a mass grave with the remains of at least 78 Yazidi women from Kocho village believed to be executed by ISIL militants.

[23][24] Following the recapture of Sinjar, Yazidi groups engaged in revenge looting and burnings targeting Sunni Muslims, as well as reprisal killings.

[27] Peshmerga forces withdrew from Sinjar on 17 October 2017, allowing the Iraqi Army and the Popular Mobilisation Units (PMU) to enter the town.

The control of the town was handed over to the PMU-backed Yazidi group called "Lalesh Brigades" after Peshmerga's withdrawal.