The decades around 1900 were crucial in the evolution of modern medical and social sciences, and in the formation of various national health services systems. The modern fields of psychiatry and mental health care are located at the intersection of these spheres. There emerged concepts, practices, and institutions that marked responses to challenges posed by urbanization, industrialization, and the formation of the nation-state. These psychiatric responses were locally distinctive, and yet at the same time established influential models with an international impact. In spite of rising nationalism in Europe, the intellectual, institutional, and material resources that emerged in the various local and national contexts were rapidly observed to have had an impact beyond any national boundaries. In numerous ways, innovations were adopted and refashioned for the needs and purposes of new national and local systems.