The king of the Qin state( 秦国 ), Yinzheng( 赢政 ), conquered the other six seigneurs through ten years of wars and brought an end to the riotous Warring States Period in 221 BC. He built up the Qin Dynasty ( 秦朝 ) - the first unified, multi-national, autocratic and power-centralized state in Chinese history. Yinzheng ( 赢正 ) then became the first emperor of the Qin Dynasty and name himself Shi Huangdi ( 始皇帝 ). The Qin is sometimes called the Ch'in, which is probably where the name China originated.

In consolidating power, Yinzheng imposed the State of Qin 's centralized, non-hereditary bureaucratic system on his new empire instead of the Zhou's feudalistic one. The Qin Dynasty relied on the philosophy of legalism . Centralization, achieved by ruthless methods, was focused on standardizing legal codes and bureaucratic procedures, the forms of writing and coinage, and the pattern of thought and scholarship. Characters from the former state of Qin became the standard for the entire empire. The length of the wheel axle was also unified and expressways standardized to ease transportation throughout the country. The Qin is also famous for the terra cotta army ( 兵马俑 ) that was found at the burial site for Shi Huangdi. The army consisted of 6,000 pottery soldiers that protected the tomb. They may be a replacement for the actual people who had previously been buried with the rulers.

To prevent future uprisings, Qin Shi Huang ordered the confiscation of weapons and stored them in the capital. In order to prevent the resurgence of feudal lords, he also destroyed the walls and fortifications that had separated the previous six states. A national conscription was devised: every male between the ages of seventeen and sixty years was obliged to serve one year in the army. Qin aggrandizement was aided by frequent military expeditions pushing forward the frontiers in the north and south. To fend off barbarian intrusion, the fortification walls built by the various warring states were connected to make a wall; this was an early precursor of the 5,000- kilometer-long Great Wall ( 长城 ) of China built later during the Ming Dynasty ( 明朝 ) . A number of public works projects, including canals and bridges, were also undertaken to consolidate and strengthen imperial rule.

Despite all of these accomplishments, Shi Huangdi was not a popular leader. The public works and taxes were too great a burden to the population. Also, the nobility disliked him because they were deprived of all their power and transplanted. Finally, he banned all books that advocated forms of government other than the current one. The writings of the great philosophers of the Spring and Autumn Period and Warring States Period were burned and more than 400 opponents were executed.