The book covers the history of Buddhism among the Oirats in the 13th-17th centuries. Buddhism had a significant impact on the politics, culture, worldview and lifestyle of these West Mongol tribes, who founded three independent states in Eurasia in the 17th-18th centuries, in which Tibet, represented by the lamas of the Kagyu and Geluk schools, had a significant influence. The monograph, based on an analysis of a large volume of sources and literature, first examines the ethno-confessional composite history of Buddhism among the Oirats, the reasons for their success with a particular Tibetan Buddhist school, highlights the role of individual lamas in disseminating the teachings of their schools, attempts to identify the role of tantrism and shamanism, consider other features of Buddhism among the Oirats.