In this study we attempt to describe and to analyze broadly urbanization in Russia and the USSR during the present century. To measure urbanization data were gathered from Russian, Soviet, and East European censuses according to a comparable definition and comparable territorial units. Despite very great population losses owing to war and famine in this century, urbanization increased at a remarkable rate, even greater than that of the United States. Between 1897 and 1959, the urbanization process was especially dynamic in four regions--Ural, Central, West Siberia, and Donetsk-Dnepr--and, in general, the east experienced a greater increase than the west. Since 1959, however, this latter trend has been reversed. Our analysis demonstrates that this urbanization was, in general, related to three complexly interrelated factors-industrialization, transportation accessibility, and in-migration. [ABSTRACT FROM AUTHOR]