On January 1, 1863, two years into the Civil War, President Abraham Lincoln issued the Emancipation Proclamation. The proclamation freed all slaves in the confederate states. Two years later, On December 6, 1865 the states abolished the institution of slavery forever by ratifying the Thirteenth Amendment: "Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction." .
The 14th Amendment to the Constitution, ratified in July 1868, guaranteed basic civil rights to all citizens; it was intended to persuade Southern states to grant suffrage to blacks by threatening a reduction of their congressional representation. To further the cause of black suffrage, the Radical Republican Congress, which had swept away the Southern regimes organized under presidential Reconstruction, required Ex-Confederate States to adopt new state constitutions allowing black suffrage before senators and representatives from those states would be readmitted to Congress. The United States was thus faced with a situation in which all the Ex-Confederate States granted blacks the right to vote, while 16 of the loyal Union states still denied black suffrage. .
To remedy the inequity and to help shore up the Southern Radical Republican Reconstruction regimes, a 15th Amendment to the Constitution was proposed in February 1869. It stated simply that "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude." There was much debate in Congress about what should be included in the Amendment. Henry Adams remarked that the 15th Amendment was "more remarkable for what it does not than for what it does contain." .
It did not guarantee blacks the right to hold office, which many congressmen felt should be included.