How did Jim Crow undo the work of Reconstruction for Black Americans?

Jim Crow & Reconstruction

During Reconstruction (1865-1877), Americans faced the daunting task of restoring order in the South, reunifying a war-torn nation, and extending equality to African Americans. The federal government passed a series of constitutional amendments aimed to extend rights and citizenship to emancipated slaves—the 13th Amendment (1865) outlawed slavery, the 14th Amendment (1868) extended citizenship to all persons born in the United States and reaffirmed equal protection of the laws to all citizens, and the 15th Amendment (1870) protected the suffrage of citizens regardless of race.

Although African Americans and their allies had made great strides in the years during which federal armies occupied the South, many of these accomplishments were reversed during the years after Reconstruction. The fate of African Americans was gradually turned over to individual states, many of which adopted restrictive 'Jim Crow' laws that enforced segregation based on race and imposed measures aimed at keeping African Americans from voting booths. White supremacist groups such as the Ku Klux Klan—who often had the cooperation of the courts and the police— used violence and terror to strip African Americans of their rights and dignity

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