Abu Nasr Qara Yusuf Nuyan (died 1420) son of Qara 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 (1400–1405). ==The Jalayirid vassalage broken== At the beginning of Qara Yusuf`s reign, the Kara Koyunlu were vassals of the Jalayirid dynasty in Ba....