In recent years psychiatric research has rediscovered the theoretical and clinical importance of opiates, especially for the understanding of depressive disorders. However, opiate treatment is not a new therapeutic concept in psychiatry. The use of opium for “melancholia” and “mania” may be traced to ancient classical medicine. After Paracelsus and Sydenham, the psychiatry of the German Romantic Era widely discussed therapeutic opium use with the Engelken family going on to develop a structured opium treatment of depression in the first half of the nineteenth century. Although the underlying scientific problems of psychiatric opium therapy were never solved, it gained an outstanding position as a practical treatment for over 100 years.