This dissertation investigates development and changes of religious ecology in post-Mao China through a study of the uneven growth of popular religion, Buddhism, and Protestant Christianity in Lanxi County in Southeast China. The central question of this study is: Why has the growth of popular religion and Buddhism been eclipsed by Protestantism in the last three decades to the point that a major reconfiguration of the Chinese religious ecology is taking place? The study also probes into each religion and addresses its internal variations.My theoretical scheme maintains that the growth and decline of a religion depends on how the religion's patterned dynamics of growth---I call them modes of operation or mechanisms of religious growth---has played out in the sociopolitical contexts, that is, the nature of the state, the nature of the society, and the relationship between the state and the society. In my study, the three religions all have distinctive modes of operation, through which religions are marshalling resources to maintain themselves and expand. How the modes of operation unfold depends on how religious actors interact with the state and the society. Because of the intrinsic characters of the religions and their historical legacies, the three religions have different relationships with state actors under the same state regulatory framework of religious affairs. The nature of the post-Mao Chinese state also shapes the ways that the religious competition is taking place. The extent and forms of religious competition cast influence on the dynamics of religions in the field. The three religions are also embedded in the society in different ways, which lead to different advantages for their growth.My study also argues that it is only in the sociopolitical context and at the particular historical juncture that Protestantism's mode of operation is able to gain great advantages and leading to the ascendance of this religion in post-Mao China.