In the autumn of 209 BC, a heavy rain kicked off the peasant war at the end of Qin Dynasty. However, at the beginning of the war, the troops of the Qin Empire against the insurgents turned out to be a miscellaneous army composed of prisoners. Qin unified China with its powerful fighting capacity. Then, why did the Qin empire use the miscellaneous army to resist the insurgents, instead of its most powerful regular army?

It turned out that at the beginning of the war to overthrow the Qin Dynasty, the two strongest armies in Qin Jun fought against the Huns in the north and attacked Lingnan in the south, so it was impossible to get back to defend Xianyang overnight. There are only fifty thousand defenders in Xianyang. Faced with hundreds of thousands of insurgents, the disparity in strength forced Qin Ershi to release 200,000 prisoners and form a miscellaneous army to resist. But why didn't Qin Jun's two regular armies with super fighting capacity save the fate of overthrowing the Qin Empire to the end?

According to Records of the Historian Sima Qian's Biography of South Vietnam, there were 500,000 Qin troops attacking Lingnan in the south at that time. After the uprising broke out, Ren Xiao, the chief of the Southern Army, sent people to Xianyang to inspect the situation. It was found that under the fatuous rule of Qin Ershi and Zhao Gao, Xianyang fell into chaos. So he ordered the army not to go north to fight to save its strength. Later, Ren Tao's subordinate, Zhao Tuo, paid tribute to his soldiers, established a separatist regime in Lingnan and established Nanyue State. At this point, this Qin Jun never went north to the Central Plains again. The main force in northern Qin Jun is 300,000 elites, guarding along the Great Wall. When the capital was in a state of emergency, the Qin Jun started to drive south, but the speed was very slow.

The reason may be that Qin Ershi and Zhao Gao killed their respected general Meng Tian. Most importantly, Qin Shihuang made himself the brain of this powerful Qin Jun through excessive centralization. After his death, this Qin Jun had only strong limbs, lost unified command and didn't know how to act. Later, the 300,000 northern main forces and the 200,000 miscellaneous army joined together. Although he defeated the insurgents several times after the meeting, he was finally defeated by Xiang Yu, a descendant of Chu nobles, in the decisive battle of Julu. At this point, the generals of the Empire State Building in the Qin Dynasty, no matter how powerful Qin Jun was, could not recover.