Friedrich Ratzel (1844-1904), German geographer and a founder of modern political geography, the study of the influence of environment on politics. Ratzel was first a journalist travelling in Europe (1869) and then in Cuba, Mexico, and the United States (1872-1875). In 1886 he became Professor of Geography at the University of Leipzig. His Anthropogeographie (2 vols., 1882-1891) and Politische Geographie (1897) stress the determining power of the physical environment in conditioning human activity.