http://www.pbs.org/wnet/jimcrow/stories_events_14th.html
The Fourteenth Amendment Radified, 1868
The Fourteenth Amendment was one of three amendments to the Constitution adopted after the Civil War to guarantee black rights. The Thirteenth Amendment abolished slavery, the Fourteenth granted citizenship to people once enslaved, and the Fifteenth guaranteed black men the right to vote. The Fourteenth Amendment was passed by Congress in June 1866 and ratified by the states in 1868. The Radical Republicans had been battling with Andrew Johnson for control of Reconstruction. Johnson was in favor of leaving the future of black people in the hands of white Southerners.
Radical Republicans disagreed, and they won. The amendment was designed to grant citizenship to and protect the civil liberties of recently freed slaves. It did this by granting citizenship to anyone born in the United States and prohibiting states from denying or abridging the privileges or immunities of citizens of the U.S., depriving any person of his life, liberty, or property without due process of law, or denying to any person within their jurisdiction the equal protection of the laws.
("No state shall make or enforce any law which shall abridge the privilegesor immunities of citizens of the United States; nor shall any state deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.") With the exception of Tennessee, the Southern states refused to ratify the Fourteenth Amendment. The Republicans then passed the Reconstruction Act of 1867, which set the conditions the Southern states had to accept before they could be readmitted to the union, including ratification of the 14th Amendment.

Since Reconstruction, the Fourteenth Amendment -- especially the equal protection clause -- has been applied to a number of cases. It emerged in the famous Brown v. Board of Education of Topeka when the United States Supreme Court used the Fourteenth Amendment as one of its rationales for declaring school segregation unconstitutional. 

-- Richard Wormser