Yeats’s Crazy Jane draws on the tradition of the Hag in Celtic mythology. The Cailleach of Beara, or the Hag of Beara, embodies one dimension of the tripartite Celtic Goddess trinity. With the Maiden and the Mother, the Hag completes the incarnation of one of Irish mythology’s most powerful forces. Associated with winter, the Hag of Beara reigns from Samhain through Beltaine, or from the first of November to the first of May. She spends the summer months transformed into a clammy boulder perched on cliffs facing the ocean, where she waits for the return of her husband, the King of the Sea, Manaan mac Lir.

Such a powerful Celtic force needed taming within in Ireland’s Christianization narratives. Incoming Roman priests realized the significant role of Irish mythic figures, so they provided additional stories to explain to the native Irish the replacement of these figures with Catholic saints and martyrs. In one such story, the Cailleach, defender of the old ways, steals St. Caithighearn’s prayer book. Awakened by a local pious witness, the saint pursues the Cailleach, retrieves her prayer book, and turns the Cailleach to stone, setting her to face the sea. Stories fashioned by the church thus layered Catholic dominance over mythical figures.