Zhao Gao is the only eunuch in the history of China to have been appointed prime minister. He hailed from the state of Zhao was said to be distantly related to the ruling house. According to the Shiji, Zhao Gao’s parents committed crimes and were punished. Both Zhao Gao and his brother were made eunuchs. However Qin Shi Huang valued Zhao Gao, since he was an expert in law and punishment. Zhao Gao enjoyed a steady rise in position.
There is a conspiracy theory that Zhao Gao was a descendant of the royal family of the Kingdom of Zhao, which was destroyed by Qin, and Zhao Gao was seeking revenge on Qin. With Zhao Gao in charge of the Qin government, it was natural that the Qin Empire collapsed in such a short time. In fact, Zhao Gao killed all the sons and daughters of Qin Shi Huang, including the Second Emperor, Huhai.