Empress Jingū 神功 appears in the eighth century Japanese chronicles as a ruling empress and a shaman. Her supposed conquest of the Korean peninsula was accomplished by the divine assistance of the various kami (gods) she invokes. Centuries later, with the growing influence of Buddhism and the development of honji suijaku 本地垂迹 theory in medieval Japan, Jingū’s story was reimagined with the addition of various Buddhist elements. Here, I explore how the Hachiman gudōkun 八幡愚童訓 (kō text, 1308–1318), the origin narrative of shrine-temple complex Iwashimizu Hachimangū, reinvents this early legend along Buddhist lines. The Gūdokun presents Empress Jingū as the Sacred Mother Bodhisattva, a manifestation of Amida Buddha, and a cakravartin. By altering the roles of Empress Jingū, as well as employing a Buddhist worldview, the text recast the whole story as one of Buddhist salvation and contributed to Jingū’s growing image as a goddess of childbirth.