Mawsillu (lit. 'from Mosul';[1] Azerbaijani: Mosullu; Turkish: Musullu) was a Turcoman tribe active in Aq Qoyunlu and the Safavid Empire.
According to Turkish historian Tufan Gündüz and John E. Woods, they one of the three biggest tribes dominating Aq Qoyunlu along with Purnak and Bayandur tribes.[2] Their main controlled areas were near Diyarbakr and Erivan. They supported Hamza beg (a son of Qara Yuluq Osman) and Sheykh Hasan at earliest times but later changed their allegiance to Uzun Hasan after 1451 during Aq Qoyunlu succession crisis.[3] They acquired the city of Ruha in later in 1475 following the defeat of Uways (brother of Uzun Hasan).
After the conquests of Ismail I they were important players in the Qizilbash administrative structure with Ismail twice marrying into the tribe and his successor, Shah Tahmasp I being born to a Mawsillu mother.[4]