Since Freud's earliest psychoanalytic theorization around the beginning of the twentieth century, the concept of the unconscious has exerted an enormous influence upon psychoanalysis and psychology, and literary, critical and social theory. Yet, prior to Freud, the concept of the unconscious already possessed a complex genealogy in nineteenth-century German philosophy and literature, beginning with the aftermath of Kant's critical philosophy and the origins of German idealism, and extending into the discourses of romanticism and beyond. Despite the many key thinkers who contributed to the Germanic discourses on the unconscious, the English-speaking world remains comparatively unaware of this heritage and its influence upon the origins of psychoanalysis. Bringing together a collection of experts in the fields of German Studies, Continental Philosophy, the History and Philosophy of Science, and the History of Psychoanalysis, this volume examines the various theorizations, representations, and transformations undergone by the concept of the unconscious in nineteenth-century German thought.