Mississippi's readmission to the United States in 1870 followed a tumultuous period during the Reconstruction Era, which began after the conclusion of the Civil War. The federal government imposed military control on the Southern states to maintain order and enforce civil rights protections for newly freed African Americans. By 1870, following the end of military governance in Mississippi, the state was required to meet specific conditions to regain its status as a Union state. In particular, Mississippi had to draft a new constitution that provided for the enfranchisement of black men.

The state's new constitution, adopted in 1868, was a critical document in establishing civil rights, although implementation was fraught with challenges. The U.S. Congress, enacting the Enforcement Acts, sought to oversee the transition and ensure that Southern states complied with federal mandates regarding civil rights. As Mississippi’s re-entry progressed, political dynamics shifted significantly; the Republican Party gained ground in a region that had been historically Democratic before the Civil War.

As Congress approved Mississippi's readmission, the national landscape shifted further towards the recognition of African American citizenship rights, although resistance from white supremacists and the emergence of Jim Crow laws in subsequent years would severely undermine these gains. This readmission was not just a local shift; it had broader implications about the direction of Southern politics and race relations in America as a whole.