Theories and data are examined concerning the rapid spread of the public school system across the United States during the nineteenth century. In the first part of the report the authors review and criticize current interpretations of the development of public education. According to these theories public schooling arose from the class conflicts and elite interests of a developing urban society--the pressures for social control of new working classes, immigrants, and young people freed from traditional constraints. In the second part of the report the authors argue that the spread of schooling can be seen as one of a series of social movements by which the American nation was built, not as a result of state or central elite action. To test their arguments the authors analyzed state-wide data on educational organization and expansion taken from reports of the Commissioner of Education and from the U. S. Census for the years 1870-1930. They found dramatic educational differences between northern and southern states which they attribute to differences in the regions' political and economic systems. The rapid spread of schooling in rural areas of the north and west is seen to reflect a commonly-held ideology of nation-building that combined the outlook of small entrepreneurs in a world market with evangelical Protestantism and an individualistic philosophy. (Author/AV)