The Primordial Mother occupies a foundational position in depth-psychological thought, designating the pre-differentiated, all-encompassing feminine principle that precedes the emergence of consciousness, individuation, and the separation of opposites. Erich Neumann, the figure whose work most systematically elaborates this concept, traces the Primordial Mother to the uroboric condition itself—the darkness, the Great Round, the nocturnal abyss from which light, sun, and ego-consciousness are born as children. She is not merely a mythological deity but the psychic substrate of all creation: ocean, earth, underworld, and primeval water converging in what Neumann calls ‘primordial darkness,’ the mother of all things. Jung, working at a higher level of abstraction, frames the mother archetype as containing both its cherishing and devouring poles—the ‘loving and terrible mother’—while Sankhya philosophy crystallizes this ambivalence into the concept of prakrti. Harvey and Baring root the figure in Paleolithic material culture, identifying spiral, oval, and serpentine forms as its earliest signatures. Campbell extends the analysis into Hindu cosmology, where the goddess speaks as the ground of all existence. The central tension in the corpus lies between the Primordial Mother as an inexhaustible source of nourishment and transformation and as the archaic, devouring darkness that must be overcome for consciousness to individuate—the very force that heroic development must both honor and transcend.