The Warring States period in Chinese history (c. 475 – 221 BC) comprises the final centuries of the Zhou dynasty (c. 1046 – 256 BC), which were characterized by warfare, bureaucratic and military reform, and political consolidation. It followed the Spring and Autumn period and concluded with the wars of conquest that saw the state of Qin annex each of the other contender states by 221 BC and found the Qin dynasty, the first imperial dynastic state in East Asian history.
While scholars have identified several different dates as marking the beginning of the Warring States period, Sima Qian's choice of 475 BC is the most often cited. The era largely corresponds to the second half of the Eastern Zhou period, where the king of Zhou formally ruled as Chinese sovereign, but had lost political power and functioned in practice as a figurehead. This dynamic served as the backdrop for the machinations of the eponymous Warring States. The label "Warring States period" derives from the Record of the Warring States, a work of history compiled during the early Han dynasty (202 BC – 220 AD).