Spirit Power explores the manifestation of the American Century in Korean history with a focus on religious culture. It looks back on the encounter with American missionary power from the late nineteenth century, and the long political struggles against the country’s indigenous popular religious heritage during the colonial and postcolonial eras. The book brings an anthropology of religion into the field of Cold War history. In particular, it investigates how Korea’s shamanism has assimilated symbolic properties of American power into its realm of ritual efficacy in the form of the spirit of General Douglas MacArthur. The book considers this process in dialog with the work of Yim Suk-jay, a prominent Korean anthropologist who saw that a radically cosmopolitan and democratic world vision is embedded in Korea’s enduring shamanism tradition.