[1][2] Husam al-Din played an important role in Saladin's war against the Crusaders and conquest of Levant and Upper Mesopotamia.
Husam al-Din Abu'l-Hayja was born in Erbil, a Kurd hailing from Hadhbani tribe.
[2] Abu'l-Hayja was the Ispahsalar of the Kurdish Mihraniyya corps, and tribal chief of Hadhbani tribe.
Abu'l-Hayja’ was sent to go into exile, abandoning the Ayyubids, he went to Iraq to seek service with the Abbasid Caliphate.
The caliph sent him against the Eldiguzid ruler of Adharbayjan, Muzaffar al-Din Uzbek, who by that time was occupying Hamadan.
[2] For his monstrous obesity and courage, extra-size bowls fabricated in Baghdad were called Abu'l-Hayja in honour of him.