The early eugenics movement and emerging professional psychiatry: conceptual transfers and personal relationships between Germany and North America, 1880s to 1930s.

French-Austrian psychiatrist Bénédict Augustin Morel's (1809-1873) Traits des dégénérescences physiques, intellectuelles et morales de l'espèce humaine (1857) was fully dedicated to the social problem of "degeneration" and it became very attractive to German-speaking psychiatrists during the latter half of the 19th century. Auguste Forel (1848-1931) and Constantin von Monakow (1853-1930) in Zurich integrated Morel's approach and searched for the somatic and morphological alterations in the human brain; a perspective of research that Ernst Ruedin (1874-1952) at Munich further prolonged into a thorough analysis of hereditary influences on mental health. This paper investigates the continuities and major differences within some early eugenic traditions of the emerging field of psychiatry in the German-speaking countries and North America.