Abu Nasr Qara Yusuf Nuyan ibn Muhammad was the ruler of the Kara Koyunlu or Black Sheep Turkomans from c.1388 to 1420, although his reign was interrupted by the Timurid invasion (1400–05).
Read more about Qara Yusuf: The Jalayirid Vassalage Broken, The Timurid Invasion, After Timurids, The Conquest of Baghdad