Preface -- Introduction: The American variations, 1900 to 2000 -- How America expanded education and why it mattered -- Where Americans came from : race, immigration, and ancestry / with Aliya Saperstein -- How Americans lived : families and life courses in flux / with Jon Stiles -- How Americans worked : new workers, new jobs, and new differences -- What Americans had : differences in living standards / with Jon Stiles -- Where Americans lived : the redrawing of America's social geography / with Jon Stiles -- How Americans prayed : religious diversity and change -- When Americans disagreed : cultural fragmentation and conflict -- Conclusion: the direction of Americans' differences -- Appendix A: Combining parametric and nonparametric regressions to study how trends differ among subpopulations -- Appendix B: Income differences or income ratios? -- Appendix C: Procedures and data for the fragmentation analysis in chapter 9 / by Jane Zavisca.