Detailed demographic characteristics of the population of the United States from 1870 to 1960 are contained in this data collection. Included are state-level estimates of the nation's inhabitants by sex, race, nativity and age, as well as intercensal migration calculated by age, race, and sex. The basic information recorded in this collection was obtained from the decennial censuses of the United States or estimated by the principal investigators from material collected by the decennial censuses. The collection is comprised of thirteen separate data files. Each contains information for every state in the nation. All parts have a rectangular file structure with one record per case, with the number of cases ranging from 50 to 2,891, and the record length from 203 to 2,930 per part. Standard geographic identifying codes used in all of the files permit the combination of 2 or more of the files as research interests dictate.