this article explores the spiritual culture of the Oirats against the backdrop of major historical transformations during the Yuan and early Ming dynasties. The authors briefly examine the shift in the Oirats religious beliefs from the shamanism that prevailed in the pre-Mongol period to the gradual adoption of Buddhism through migration and contact with other cultures. Our research reveals that the Oirats developed a rich culture encompassing an epic heritage and a body of mythological and religious concepts. The article traces the role of political and cultural factors, including the participation of the Oirats in the conquest policy of Genghis Khan, their integration into the cultural system of the Mongol Empire, as well as the further rise of Oirat rulers in the Ming era. Attention is also given to the consolidation of Buddhism, which began to take hold under Toghon and became the state religion under Esen. Moreover, Esen employed high-ranking Buddhist monks in the capacity of state preceptors, underscoring the alignment of the nations ideological framework with the strengthening of relations with the Ming dynasty. Historical sources confirm active diplomatic exchanges between the Oirats and Ming China. It is concluded that the Oirats’adoption of Buddhism played a decisive role in preserving their ethno-cultural integrity and fostering unity amidst interethnic interactions.