Between the American Revolution and the Civil War, a caste of free Negroes arose in the South. Its size and character constantly changed, observes Berlin, who has written the study not as a hypertrophied doctoral thesis, but as one means of access to general ""Southern attitudes on race and class."" In southern urban centers (where just after the Revolution an ""Afro-American"" cult sprang up), manumission and self-purchase increased the numbers of free Negroes; during the 1820's more anti-slavery societies existed in the upper South than in the North, while among those who ""desired to be rid of all free Negroes, perhaps all Negroes,"" the colonization idea took hold. The marginal economic position and legal restrictions on free Negroes are surveyed along with the less familiar extent of interracial friendship and the antebellum version of white protectorship. In the 1850's, general prosperity benefited the free blacks, but with the new consolidation of pro-slavery militancy, demands crested for expulsion of the freedmen -- demands which, Berlin says, created great outrage among the mass of southern whites on grounds of both economic self-interest and humanitarianism. Less psychologically penetrating than Eugene Genovese's studies of the slave South, and less innovative than Robert Starobin's work on industrial slavery, both of which shaped this book, it is nevertheless a real contribution. The topic has been fruitfully extended beyond its limits and the book achieves a vivid sense of the period as a whole.