My talk examines heterodoxy’s place in genealogies of secularism, focusing on the work of Russian occultist H. P. Blavatsky, who, I hope to show, was first and foremost a theorist of religion. A key point of Blavatsky’s critique was that Christianity’s triumphalist narrative consigned competing theories of the world to oblivion by denouncing them as heresies. These so-called heresies were, for her, lost or esoteric knowledge. The fact that they referred in equal measure to religious ideas both inside and outside Christianity allowed her to range across world religions in search of their esoteric core. My talk raises larger questions about what new narratives of literary history emerge when we examine late nineteenth-century religion as a much more heterogeneous formation, which included esoteric, non-traditional currents (such as Theosophy) competing with the dogmas of institutional religion.