Su refused, and asked to be transferred to another commandery instead. Yu in turn refused and prepare for war. Su then declared a rebellion against Yu's regency, stating, in a famous quote:  In other words, he would rather lose in battle and be executed, than to submit himself to what he thought was certain imprisonment. He allied himself with Zu Yue () the governor of Yu Province (, usually referring to modern eastern Henan, but by that point mostly confined to central Anhui), and headed for Jiankang. Yu was confident he could defeat Su—so much so that he declined emergency assistance from Wen Jiao, who was then the governor of Jiang Province (, modern Jiangxi) -- but instead Su won battle after battle and reached Jiankang quickly, capturing the city and forcing Yu to flee. Su's forces pillaged the capital, stripping both officials and commoners of their wealths and even their clothing, and even the servant girls of Empress Dowager Yu, Emperor Cheng's mother, were seized. Empress Dowager Yu, in distress, died. (It is said that she was "humiliated" by Su, but the method of humiliation was not described.) Su took over the imperial government and put his allies into high positions quickly. However, Yu Liang, Wen, and Tao Kan soon entered into an alliance and headed back east to Jiankang. Eastern commanderies also rose against Su, led by Chi Jian (). Despite these provincial forces having greater numbers, Su continued to defeat them in battle after battle, and even Wen and Tao, capable generals in their own right, became apprehensive. However, during one battle in late 328, Su was hit by a spear and fell off his horse, and the provincial forces quickly beheaded him. His forces tried to coalesce behind his brother Su Yi (), but collapsed in early 329.