Through an analysis of leading British medical journals during the Second World War, this article argues that psychiatric understandings of the “war neurosis” suffered by British servicemen during that conflict were predicated on a notion of the “neurotic serviceman” as an objective personality type predisposed to break down during the strain of wartime. By discounting the effects of traumatic war experiences in favour of an aetiology that located the genesis of psychiatric disorder within the inherently unstable individual, such an approach minimized the influence of the martial environment in favour of heredity and the events of early childhood as the ultimate arbiters of mental stability in service personnel.