The death of Kara Koyunlu ruler Qara Yusuf in 1420 had left his sons Ispend bin Yusuf, Qara Iskander, Jahan Shah and Abu Sa’id bin Yusuf fighting over the succession.
The Sa’dlu tribe, one of the main sub-tribes of the Kara Koyunlu, had declared Ispend as the new chief.
Abu Sa’id had to flee and Jahan Shah had gone to Baghdad.
Qara Iskander was thus left with Azerbaijan and Tabriz as its capital while Ispend was left with Iraq with Baghdad as his capital.
Iskander and Ispend had joined together to fight the Ak Koyunlu who were invading from the west, and defeated them.
The Timurid Shah Rukh takes advantage of the weakened state of the Kara Koyunlu to invade their land, crossing the Aras River and defeating the forces of Iskander and Ispend in a battle at Yahsi on July 28–29, 1421.
He briefly occupies Azerbaijan and Armenia, then withdraws once more to Khorasan.
At this point, Ispend quickly reoccupies Tabriz.
However, Iskander follows him and fights with him, taking the city and establishing himself as ruler of the Kara Koyunlu.
