Yang Liang
An immediate challenge that Emperor Yang faced was a rebellion by his brother Yang Liang, then the commandant at Bing Province, who was encouraged by the generals Wang Kui () and Xiao Mohe. Yang Liang received support from 19 provinces, but lacked a coherent plan as to whether to try to challenge Emperor Yang for the control of the entire empire, or just the region north of the Yellow River. After some initial successes, Yang Liang's offenses stalled. Emperor Yang sent Yang Su against him, and Yang Su proceeded quickly to Yang Liang's headquarters at Bing Province, capturing Xiao and forcing Yang Liang to surrender. Emperor Yang did not execute Yang Liang, but reduced him to commoner rank and imprisoned him for the rest of his life.