In the 71st year of the Ming Dynasty, the third emperor Xiao Ye was foolish and old, obsessed with women and did not come to the court for a long time. In addition, natural disasters were frequent, and riots broke out for a while.The King of the Huns in the northern border was Tuoba Hongtu, who was once almost exterminated by Emperor Wu of the Ming Dynasty, rose in the desert. He fought all the way between the tribes in the desert without losing. In less than five years, he unified the northern border. The King of the Huns, known as the Light of the Northern border, worked hard to govern but was uneasy. At the beginning of the spring of the 78th year of the Ming Dynasty, he led 50,000 troops south, defeating 200,000 Ming troops. For a time, the court and the country were in full swing, and wars rose everywhere.Emperor Xiao Ye hurriedly assembled a large army of 300,000 and ordered the veteran general He Tonghu as the commander to block the Huns outside Yanmen Pass. However, Tuoba Hongtu was treacherous and treacherous, and led 30,000 surrendered troops to lure He Zhuang all his main forces out and set up an ambush at Hululing outside Yanmen Pass. It was successful in one battle. In this battle, all 300,000 elite troops were lost. The veteran general He Tonghu committed suicide and died. The Huns' cavalry came straight down and rushed towards the last pass outside the capital, Datong Prefecture!