窦建德
Meanwhile, Yuchi Yichen made an attempt to destroy the rebels north of the Yellow River, but while he enjoyed some successes, Emperor Yang and his prime minister Yu Shiji, fearing Yuchi Yichen's military strengths, recalled him under guise of a promotion, allowing the rebel activities north of the Yellow River to reinvigorate themselves and become difficult to control, under the leadership of Dou Jiande.