This chapter analyzes why very few historians in twentieth-century Britain engaged with psychoanalytic theories of the mind. It also examines why most celebrated Marxist historians paid so little attention to Freud. Psychoanalysis, of course, has a diverse history; thus, for its serious critics it represents something of a moving target. As is well known, the social, political, cultural and psychological convulsions of World War I and its aftermath coincided with and, in part, stimulated the expanding theoretical and clinical vocabulary of the Freudian movement. Early twentieth-century history was not fertile soil for psychoanalysis. In the decades after World War II no major British historian declared psychoanalysis to be the new frontier. The chapter considers a striking pattern wherein psychoanalytic ideas are nonchalantly dismissed or occluded. Psychoanalysis transforms the way of conceptualising psychic organisation, as well as its relationship to the unconscious 'logic' that informs and skews political choices and allegiances.