宇文化及
There was no evidence that suggested that Yuwen Huaji permitted Yang Hao to actually exercise any imperial powers. Yuwen Huaji soon abandoned Jiangdu and led the remaining Sui court and the elite Xiaoguo Army () north. During the procession, Yang Hao was effectively put under house arrest at the mobile executive bureau (尚書省, "Shangshu Sheng"), under heavy guard. Edicts were signed by Yang Hao, but he was not even permitted to meet with the officials. Yuwen Huaji soon engaged the rebel leader Li Mi but suffered several defeats against Li and eventually forced to withdraw to Wei (魏縣, in modern Handan, Hebei). As he saw his military power waning, he became depressed. He then resolved to be emperor while he was still alive, and therefore poisoned Yang Hao, declaring himself emperor of a state of Xu.