This essay offers a first critical reading of American author Fanny Van de Grift Stevenson’s short story “The Warlock’s Shadow” (1886), asserting that the tale appropriates historical traumas in order to navigate, and transgress, boundaries of genre and gender. The strangeness of the text’s Central Californian setting, to the narrator, precipitates a series of Gothic metamorphoses, and “The Warlock’s Shadow” engages with this transformation via a concept that this essay defines as the “Californian Uncanny”. The latter framework is a result of the specific, layered indigenous and colonial identities of post-Gold Rush California coming into contact with the unstable subjectivities of the Gothic genre. “The Warlock’s Shadow” manifests the Californian Uncanny primarily through the relationship between the home, the environment, and the “unassimilable” inhabitant. Stevenson’s text illustrates, through these images, the ways in which late-nineteenth-century American Gothic fiction has allowed the white feminine subject to negotiate her own identity, complicating the binary distinctions between Self and Other which underpin American colonialism both internally and externally. The phenomenon of the Californian Uncanny in “The Warlock’s Shadow” reflects these gendered and geographical anxieties of American identity, confronting the ghosts of the nation’s westernmost region.