In the seventh year after the founding of the Northern Song Dynasty, Li Yu, the last emperor of the Southern Tang Dynasty, faced the crisis of national subjugation. Xiao Heng, the son of an old general from the previous dynasty, risked his life to remonstrate with him and offered advice to unite Wu and Yue, defend the Yangtze River, and wear down the Song army. Li Yu believed in his plan and granted him the power of navy. Xiao Heng secretly instigated rebellion against the border generals and alienated the Song army, allowing the Southern Tang Dynasty to hold on for more than a year. There were widespread internal complaints in the Northern Song Dynasty, and the Liao army took advantage of the situation to harass the border. Zhao Kuangyin was forced to negotiate a peace, and the Southern Tang Dynasty was able to protect the country. After that, Li Yu reformed the country and tried to strengthen it, and Xiao Heng assisted in political reforms. The Southern Tang Dynasty turned a corner and settled in the south of the Yangtze River for decades. It did not fall into the situation of "the motherland cannot bear to look back", and rewrote the fate of the Southern Tang Dynasty.
