Bai Qi, also known as Gongsun Qi (公孫起), was a Chinese military general of the Qin state during the Warring States period. Born in Mei, Bai Qi served as the commander of the Qin army for more than 30 years, being responsible for the deaths of over one million, earning him the nickname Ren Tu. According to the Shiji, he seized more than 73 cities from the other six hostile states, and to date no record has been found to show that he suffered a single defeat throughout his military career. He was instrumental in the rise of Qin as a military hegemon and the weakening of its rival states, thus enabling Qin's eventual conquest of them. He is regarded by Chinese folklore as one of the four Greatest Generals of the Late Warring States period, along with Li Mu, Wang Jian, and Lian Po; he is also remembered as the most fearsome amongst the four.

Qin was an ancient Chinese state during the Zhou dynasty. It is traditionally dated to 897 BC. The Qin state originated from a reconquest of western lands that had previously been lost to the Xirong. Its location at the western edge of Chinese civilisation allowed for expansion and development that was not available to its rivals in the North China Plain.