Fundamental changes occurred in chinese civilization between the fifth century B.C.E. and the second century C.E., roughly corresponding to the Warring States (which officially commences in 453 B.C.E.) and the Ch'in and Han empires (Han rule ends in 220 C.E.). The emergence and maturation of philosophical speculation and of new sociopolitical models have traditionally constituted the ground on which other elements of the contemporary civilization have been drawn. As a consequence, the nature of religious traditions during this period has been poorly understood and insufficiently studied; first, because the documentation preserved in received literature overwhelmingly reflects the politico-philosophical leanings of an elite social stratum and thus offers only a partial, biased view of the range of religious belief and practice; and second, because modern research on Warring States, Ch'in, and Han religion by and large relies on the viewpoints expressed in the received record. Whereas the study of Buddhism and, more recently, of religious Taoism and popular religion is thriving among an ever-growing number of scholars of the history of Chinese religion, the ancient period of Warring States, Ch'in, and Han is still dominated by scholars engaged in the study of the philosophical tradition. The idea that religious belief during the period was tempered by philosophical reason is a widely shared assumption.