Historians of architecture and the applied arts in the late nineteenth century developed a peculiar notion of a borderline around 1840: before that date, they maintained, designing and building was done largely unconsciously, entailing a ‘true’ ethnicity of design, especially of workmanship, and styles emerged somehow authentically from the broadest national or regional groups - whereas from 1840 onwards everything was done consciously and artificially. The article discusses the emergence of that notion in England, Germany and France.