[15] Ain Sifni is attested as a diocese of the Church of the East in 576 AD, in which year its bishop Bar Sahde attended the synod of Catholicos Ezekiel of Seleucia-Ctesiphon.

[19] The town served as the centre of the subdistrict of Bēth Rustāqa which, as a consequence of the spread of the Syriac Orthodox Church in the district of Bēth Nūhadrā in the late sixth and early seventh centuries, was transferred to the district of Marghā in the late eighth century.

[18] The Yazidi population of Ain Sifni was forcibly relocated to Mahad in 1975 by the Iraqi government as part of its policy of Arabisation, and the town was resettled by Arabs.

[26] In the aftermath of the fall of President Saddam Hussein in 2003, the Arab settlers fled Ain Sifni, allowing its former Yazidi population to return.

[15] In January 2005, it was reported that the Kurdistan Democratic Party blocked the delivery of ballot boxes to Ain Sifni, thereby ensuring its population was unable to vote in the Iraqi parliamentary election.

[2] Most of the town's population of 16,000 people fled during the Islamic State of Iraq and the Levant (ISIL) offensive in August 2014, and under 500 men remained to defend Ain Sifni under the leadership of mayor Mamo al-Bagsri.

[11] The town was the residence of the Yazidi Emir Tahseen Said until he went into exile in Germany, where he died, and was buried at Ain Sifni on 5 February 2019.