An ethnic Turkmen born in Tal Afar, Nineveh Governorate, al-Hiyali was an Iraqi Army Colonel under Saddam Hussein.

[7][8] He also fought in the Gulf War[9] prior to his dismissal from the Iraqi Army after US forces arrived, and later joined Sunni insurgents to fight the Americans.

The biography states that al-Hiyali had renounced his loyalty to Saddam Hussein and rejected Ba'athism and left the Iraqi army to join Abu Ali al-Anbari in pledging allegiance to Ansar al-Islam, providing important logistical aid and training to jihadist networks.

He also was at the forefront of the genocide against the Yezidi people including the enslavement of the women and girls, personally raping captives[13] and executing prisoners despite pleas for mercy.

[15][16] His death was confirmed by ISIL official spokesman and senior leader Abu Mohammad al-Adnani in an audio recording posted on jihadist websites in October 2015.