By the time the Civil War ended, the South was devastated. Its money was worthless, its economy ruined, and over 30% of its population was dead. Slavery, which had propped up the South for so long, had been abolished, and the South was forced to accept a humiliating defeat. But if all this wasn't enough, what happened next added insult to injury.
The South was now under Northern control, and, since most Democrats had left the Union, this left the Republican Party in charge of the South. The “Radical Republicans,” as they were called, passed legislation that treated the South as conquered territory. The South was divided into 5 districts, each ruled by a military governor whose powers included punishing and even executing people without a trial, and confiscation and redistribution of private property. All those who had fought for or sympathized with the Confederacy were stripped of their citizenship, their voting rights, and the right to participate in government or run for public office. In short, the Southern states ceased to exist as part of the Union, and were banned from reinstatement unless they ratified the 14th amendment, which gave blacks citizenship and voting rights. Troops were dispatched to the South to enforce the proper treatment of black citizens.
Although corruption and abuses were not unknown, the Northern governors were, for the most part, at least somewhat understanding and lenient toward the South. However, Southerners deeply resented having black rights rammed down their throats while, at the same time, they were being stripped of their own citizenship. They were also bitter about the Northern “foreigners” they were forced to live under. The South's government now consisted of “carpetbaggers,” (Northern Republicans who moved South for political and business opportunities), and “scalawags,” (Southerners who were perceived as traitors for their collaboration with the Republican party). Most Republican voters in the South were freed blacks, and they helped elect about 2,000 black Republicans to local and state offices, including 2 senators and 17 U.S. Representatives. Being governed by former slaves further embittered the South.
In 1865, the KKK was founded, originally as a club for ex-Confederate soldiers. It rapidly became a hate group that targeted Republicans, blacks, and others, hounding and killing them. President Ulysses Grant cracked down on the Klan, succeeding in suppressing it for a while. But, when Republican Rutherford Hayes was elected president by a razor-thin margin, things changed. As part of the deal struck to put Hayes in office, Republicans agreed to withdraw from the South. It didn't take long for Southerners to undo Reconstruction. A resurgent KKK resumed its terrorism. The very system set up to protect blacks resulted in decades of further oppression and violence for them, as embittered white Southern Democrats regained power. It would be more than a century before black Americans could fully enjoy the rights that the Reconstruction Acts were intended to protect.