The Thirteenth Amendment to the U.S. Constitution, ratified shortly after the end of the Civil War prohibited slavery and involuntary servitude. But it did not specifically grant citizenship to freed slaves, and Southern states took advantage of this omission. Congress redressed the balance with the Fourteenth Amendment, which was ratified in 1868. The amendment stated that all citizens, whether by birth or by naturalization, were guaranteed equal protection under the law, and called for Federal intervention if states failed to comply. Former Confederate states that wished to rejoin the United States were required to sign the Fourteenth Amendment before being readmitted.

What the Fourteenth Amendment did not do was guarantee equal rights. Southern states used the “separate but equal” argument, which allowed them to keep blacks and whites separate as long as they did not deprive them of basic legal rights. Eventually, this arrangement led to a series of discouraging developments that relegated blacks in the South to inferior status.