Religion has been the basis of the statehood of various nations since ancient times. This article analyzes the role of the Buddhist concept of “chakravartin” (ideal universal ruler) in the political structures of the Korean statehood of the Three States period. The author believes that in the context of the decline of Confucianism against the backdrop of an ideological crisis and political fragmentation in China in the period from the beginning of the 3th century to the end of the 6th century. Buddhism, having an active political potential, has become a full-fledged ideological alternative to the teachings of Confucius. Korea, as a permanent recipient of Chinese culture, was also influenced by Buddhism, which was reflected in subsequent changes in the state ideology of the Korean states. To explore this issue further, this article provides a comparative description of the Buddhist and Confucian state theories, a list of the main socio-political factors that contributed to the acquisition of the functions of state ideology by Korean Buddhism, as well as an analysis of the state administration system of each of the three Korean kingdoms: Koguryeo, Paekche and Silla. Due to the lack of historical evidence about their state ideology in the written sources of the period, the author relies mainly on indirect sources of information – in particular, archaeological finds. Moreover, various Buddhist canonical texts were used to conduct a comparative analysis using "chakravartin"’s archetypes in other countries of the Asian region.