Although African Americans were legally freed from slavery under the Thirteenth Amendment, granted citizenship in the Fourteenth Amendment, and men elevated to the status of citizens and were granted full voting rights by the Fifteenth Amendment in the years soon after the end of the American Civil War, after the Reconstruction era, conservative Democrats regained power and imposed many restrictions on people of color in the South. At the turn of the century, Southern states passed constitutions and laws that disenfranchised most blacks and many poor whites, excluding them from the political system. The whites imposed social, economic, and political repression against blacks into the 1960s, under a system of legal discrimination known as Jim Crow laws, which were pervasive in the American South. Blacks suffered discrimination from private businesses as well, and most were prevented from voting, sometimes through violent means. Twenty-one states prohibited interracial marriage.