This dissertation concerns the cult of Mount Yudono (located in present-day Yamagata Prefecture) during the Edo period (1603–1868). In the first chapter, I take into account the historical background and religious dynamics that led to the formation of the sacred territory of the Three Dewa Mountains (Dewa Sanzan), namely Mount Haguro, Mount Gassan, and Mount Chōkai, of which Mount Yudono was considered to be the shared sancta sanctorum. The second chapter analyzes the particularities of the religious institutions that administered the territory of Mount Yudono. Specifically, I focus on the pivotal role played by a special group of ascetics that were called “permanent ascetics” (issei gyōnin) in shaping the religious identity a...