After the death of Qara Yusuf in December 1420, Shahrukh Mirza tried to take Azerbaijan from Qara Yusuf's son Qara Iskander, using the fact that none of his sons was accompanying his father. Despite defeating Iskander, twice in 1420–21 and 1429, only in the third expedition of Shahrukh Mirza in 1434–35 did the Timurids succeed, when he entrusted the government to Iskander's own brother, Jahan Shah as his vassal.[1]