Yuchi Jiong
In 580, Emperor Xuan, who had by that point become retired emperor, died, and Emperor Xuan's father-in-law Yang Jian seized power as regent over Emperor Xuan's son Emperor Jing. Yang Su became close to Yang Jian, and Yang Jian made him the governor of the important Bian Province (汴州 roughly modern Kaifeng, Henan). However, before Yang Su could report to Bian Province, the general Yuchi Jiong, suspicious of Yang Jian's intentions, rose against him.