Yang Liang
In 604, Emperor Wen died—a death that traditional historians, while admitting a lack of direct evidence, generally believe to be a murder ordered by his son, Yang Guang the Crown Prince. Yang Guang took the throne as Emperor Yang. Soon afterwards, Emperor Yang's younger brother Yang Liang the Prince of Han rose in rebellion at Bing Province (并州, roughly modern Taiyuan, Shanxi). Yang Liang's general Qiao Zhongkui (喬鍾葵) afterwards put Li Jing (李景), the commandant of Dai Province (代州, roughly modern Xinzhou, Shanxi), who remained loyal to Emperor Yang, under siege. Emperor Yang ordered Yang Yichen to try to lift the siege against Li, and Yang Yichen was successful in defeating Qiao. After Yang Liang was defeated and forced to surrender to Yang Su, Yang Yichen was given material rewards and made the governor of Xiang Province. In 607, Emperor Yang recalled him to be the director of imperial clan affairs, and later the director of husbandry affairs.