Emperor Shao honored his stepgrandmother
Xiao Wenshou as grand empress dowager, and he created his wife Crown Princess Sima Maoying as empress. The matters of the central government were largely in the hands of Xu Xianzhi, Fu Liang, and Xie Hui. One immediate matter that needed to be dealt with was that
Emperor Mingyuan of Northern Wei, hearing of Emperor Wu's death, launched a major attack on Liu Song and crossed the
Yellow River. In winter 422, Northern Wei forces captured Huatai (, in modern
Anyang,
Henan). In spring 423, they captured
Luoyang. Tan Daoji was dispatched to try to save the northern cities, and he was able to save
Shandong Peninsula from falling, but by summer 423, the last major Liu Song outpost on the Yellow River, Hulao (, in modern
Zhengzhou,
Henan), had fallen, along with
Xuchang. Only then did Northern Wei stop its advances. In fall 423, Emperor Shao honored his mother Consort Zhang as
empress dowager. By 424, Xu, Fu, and Xie had grown increasingly dissatisfied with Emperor Shao as an emperor, as Emperor Shao had failed to follow the proper behavior during the three-year mourning period for his father, but spent most of his time on games and pleasure rather than on studies and important matters of state, despite encouragement from his official Fan Tai (). They therefore considered deposing him, but they were also dissatisfied with the next ranked son of Emperor Wu, Liu Yizhen, who was talented but was even more frivolous than Emperor Shao in his behavior, often spending time with other talented but frivolous men, including
Xie Lingyun and Yan Yanzhi () and often requesting the imperial government to supply him with more and more money. They therefore stoked the rivalry that Emperor Shao already had with Liu Yizhen and then accused Liu Yizhen of crimes, and Emperor Shao reduced Liu Yizhen to commoner status and exiled him to Xin'an Commandery (, roughly modern
Hangzhou,
Zhejiang). With Liu Yizhen out of the way, Xu, Fu, and Xie prepared to remove Emperor Shao as well. Because they were apprehensive about the powerful armies that Tan and
Wang Hong had, they summoned Tan and Wang to the capital and then informed them of the plot. They then sent soldiers into the palace to arrest Emperor Shao, after first persuading the imperial guards not to resist. Before Emperor Shao could get up from bed in the morning, the soldiers were already in his bedchamber, and he made a futile attempt to resist, but was captured. He was sent back to his old palace. The officials then, in the name of Empress Dowager Zhang, declared Emperor Shao's faults and demoted him to Prince of Yingyang, offering the throne to his younger brother Liu Yilong Prince of Yidu instead. ==After removal==