Psychology as the study of mind was an established subject matter throughout the nineteenth century in Britain, Germany, France, and the United States, taught in colleges and universities and made the subject of books and treatises. During the period 1870-1914 this existing discipline of psychology was being transformed into a new, experimental science, especially in Germany and the United States. The increase in experimentation changed the body of psychological writing, although there remained considerable continuity in theoretical content and non-experimental methodology between the old and new psychologies. This paper follows the emergence of the new psychology out of the old in the national traditions of Britain (primarily England), Germany, and the United States, with some reference to French, Belgian, Austrian, and Italian thinkers. The final section considers some methodological and philosophical issues in these literatures.