This article traces the history of Reconstruction in the United States from the closing years of the Civil War through the end of federal military occupation of the South in 1877. For broader context, see American Civil War and United States - History. For interpretive debates, see United States Reconstruction - Debate.

Debate over how to reintegrate Confederate states began before the Civil War ended. President Abraham Lincoln announced his Ten Percent Plan in December 1863, under which a seceded state could re-form a loyal government once ten percent of its 1860 voters took an oath of allegiance and the state abolished slavery. Arkansas and Louisiana organized governments under this plan in 1864.

Congressional Republicans regarded Lincoln's terms as too lenient. The Wade-Davis Bill, passed by Congress in July 1864, required a majority of a state's white male citizens to take an oath of past loyalty - not merely future loyalty - before reconstruction could begin, and imposed stricter conditions on former Confederates. Lincoln pocket-vetoed the bill. Its sponsors, Senator Benjamin Wade of Ohio and Representative Henry Winter Davis of Maryland, issued the Wade-Davis Manifesto criticizing Lincoln's action.

The Thirteenth Amendment, abolishing slavery throughout the United States, passed Congress in January 1865 and was ratified in December 1865. Lincoln's second inaugural address, delivered 4 March 1865, set a tone of reconciliation toward the South.

Lincoln was assassinated on 14 April 1865, five days after General Robert E. Lee's surrender at Appomattox Court House. Vice President Andrew Johnson, a Tennessee Democrat who had remained loyal to the Union, assumed the presidency.

Johnson announced his own reconstruction plan in May 1865, offering amnesty and restoration of property - except enslaved persons - to most former Confederates who took a loyalty oath. High-ranking Confederate officials and wealthy planters required a presidential pardon, which Johnson granted liberally. Johnson appointed provisional governors in the former Confederate states and authorized them to convene constitutional conventions.

The Southern state governments reorganized under Johnson's plan moved quickly to restrict the rights and labor options of freed people. Beginning in late 1865, Southern legislatures passed laws known as Black Codes, which imposed vagrancy statutes, labor contract requirements, restrictions on land ownership, and limitations on the occupations freed people could enter. Mississippi and South Carolina enacted the most restrictive codes; other states followed with variations.

Congress, which had not been in session during the summer and fall of 1865 when Johnson implemented his plan, reconvened in December 1865 and refused to seat the newly elected Southern delegations. Several of those elected to Congress from former Confederate states had been Confederate officers or officeholders. Congress established the Joint Committee on Reconstruction to investigate conditions in the South.

The Freedmen's Bureau, established by Congress in March 1865, provided food, clothing, medical care, and legal assistance to freed people and white refugees in the South. It also supervised labor contracts and established schools. Bureau agents operated across the former Confederate states with limited personnel and resources.

In April 1866, Congress passed the Civil Rights Act of 1866 over Johnson's veto, declaring all persons born in the United States citizens and entitled to equal protection of the laws regardless of race. Congress also extended the Freedmen's Bureau over Johnson's veto.

The Fourteenth Amendment, passed by Congress in June 1866 and ratified in July 1868, established birthright citizenship, prohibited states from abridging the privileges and immunities of citizens or denying equal protection and due process of law, reduced congressional representation for states that denied the vote to adult male citizens, and disqualified former officeholders who had supported the Confederacy from holding federal or state office.

The 1866 congressional elections, held amid a widening breach between Johnson and Congress, produced large Republican majorities in both chambers, giving Republicans veto-proof control of Congress.

Congress passed the first Reconstruction Act over Johnson's veto on 2 March 1867. It declared the existing Southern state governments - other than Tennessee, which had ratified the Fourteenth Amendment - provisional and invalid, divided the ten remaining former Confederate states into five military districts each commanded by a Union general, and required new constitutional conventions elected by male citizens regardless of race, ratification of the Fourteenth Amendment, and congressional approval of the new state constitutions before a state could be readmitted to representation in Congress.

Three additional Reconstruction Acts followed in 1867 and 1868, clarifying and tightening the process. Military commanders registered voters, supervised elections, and maintained order. Freed black men registered and voted in large numbers across the South for the first time.

Congress also passed the Tenure of Office Act in March 1867, prohibiting the president from removing Senate-confirmed officials without Senate approval. When Johnson suspended and then attempted to remove Secretary of War Edwin Stanton in 1867 and 1868, the House of Representatives voted to impeach Johnson on 24 February 1868 - the first impeachment of a U.S. president. The Senate acquitted Johnson by one vote in May 1868.

New state constitutions were drafted and ratified across the South in 1867 and 1868. These constitutions established public school systems, eliminated property requirements for voting and officeholding, and in most cases did not impose racial restrictions on suffrage. Seven former Confederate states were readmitted to Congress in June 1868 following ratification of the Fourteenth Amendment. The remaining three - Virginia, Mississippi, and Texas - were readmitted in 1870 after ratifying the Fifteenth Amendment as well.

The Fifteenth Amendment, ratified in March 1870, prohibited denial of the right to vote on the basis of race, color, or previous condition of servitude.

Republican state governments operated across the South during the Reconstruction period, supported by black voters, Northern migrants known as carpetbaggers, and Southern Unionists known as scalawags. These governments expanded public education, built railroads and other infrastructure, reformed tax systems, and in some states established institutions for the poor, disabled, and mentally ill.

Black men held office at all levels of government during Reconstruction. Two black men served in the U.S. Senate from Mississippi: Hiram Revels, who served from 1870 to 1871, and Blanche Bruce, who served from 1875 to 1881. More than a dozen black men served in the U.S. House of Representatives during Reconstruction. Hundreds more held state and local offices across the South.

Violent opposition to Reconstruction governments and black political participation emerged across the South. The Ku Klux Klan, founded in Pulaski, Tennessee in 1865 and reorganized under former Confederate General Nathan Bedford Forrest in 1867, carried out widespread violence against black officeholders, voters, and their white Republican allies. Similar paramilitary organizations included the White League and the Red Shirts.

Congress responded with the Enforcement Acts of 1870 and 1871, also known as the Ku Klux Klan Acts, which made it a federal crime to interfere with constitutional rights and authorized the president to suspend habeas corpus in areas where conspiracies against federal law could not be suppressed by ordinary means. President Ulysses S. Grant suspended habeas corpus in nine counties of South Carolina in October 1871 and deployed federal troops, leading to mass arrests and the temporary suppression of Klan activity in the region.

Support for federal enforcement of Reconstruction policies weakened in the North during the early 1870s. The Liberal Republican movement, which coalesced around opposition to corruption in the Grant administration and support for sectional reconciliation, ran Horace Greeley against Grant in the 1872 presidential election. Grant won decisively, but the Liberal Republican critique of Reconstruction gained broader currency.

The Slaughterhouse Cases (1873) and United States v. Cruikshank (1876) significantly narrowed federal authority to protect civil rights under the Fourteenth and Fifteenth Amendments. In Cruikshank, the Supreme Court ruled that the federal government could not prosecute private individuals for violations of constitutional rights - only state actors - effectively limiting the reach of the Enforcement Acts.

The Panic of 1873 and the ensuing economic depression shifted political attention away from Reconstruction. Democrats gained control of the House in the 1874 elections.

The Colfax massacre of April 1873 in Louisiana, in which white paramilitary forces killed more than 60 black men following a disputed local election, was among the most lethal incidents of anti-Reconstruction violence. Federal prosecutions under the Enforcement Acts resulted in convictions that were overturned by the Supreme Court in Cruikshank.

By 1876, Republican governments had been overthrown or displaced in most Southern states through a combination of violence, economic intimidation, and electoral fraud. The disputed presidential election of 1876 between Republican Rutherford B. Hayes and Democrat Samuel Tilden was resolved by the Compromise of 1877, in which Hayes was awarded the presidency. Federal troops were subsequently withdrawn from the remaining Southern states where they had been supporting Republican governments - South Carolina and Louisiana. The Republican governments in those states collapsed, and Democrats assumed control.

The end of Reconstruction was followed by the systematic disenfranchisement of black voters across the South through poll taxes, literacy tests, grandfather clauses, and white primaries, measures that were implemented primarily in the 1880s and 1890s and codified in new state constitutions. Segregation was formalized in law through statutes that came to be known as Jim Crow laws. The Supreme Court's decision in Plessy v. Ferguson (1896) upheld legally mandated racial segregation under the separate-but-equal doctrine.

• Whether Presidential Reconstruction under Johnson represented a reasonable attempt at sectional reconciliation or an abandonment of freed people's rights is disputed among historians; see United States Reconstruction - Presidential Reconstruction Debate.
• Whether the Compromise of 1877 constituted a formal bargain between Republican and Democratic leaders or emerged from a more diffuse political process is disputed; see United States Reconstruction - Compromise of 1877 Debate.
• Whether Reconstruction governments were corrupt and incompetent or were reasonably effective administrations undermined by violence and federal abandonment is a long-contested historiographical question; see United States Reconstruction - Republican Governments Debate.
• Whether the retreat from Reconstruction resulted primarily from Northern indifference, Supreme Court rulings, Southern violence, or structural features of American federalism is disputed among historians; see United States Reconstruction - Debate.
• Whether Reconstruction should be understood as a failed revolution, an incomplete reform, or a constitutional achievement subsequently dismantled is a contested framing among historians; see United States Reconstruction - Legacy Debate.

1. Eric Foner, Reconstruction: America's Unfinished Revolution, 1863-1877 (Harper & Row, 1988). The standard modern synthesis.
2. W.E.B. Du Bois, Black Reconstruction in America, 1860-1880 (Harcourt, Brace and Company, 1935).
3. Kenneth M. Stampp, The Era of Reconstruction, 1865-1877 (Alfred A. Knopf, 1965).
4. James M. McPherson, Battle Cry of Freedom: The Civil War Era (Oxford University Press, 1988).
5. Hans L. Trefousse, Andrew Johnson: A Biography (W.W. Norton, 1989).
6. George C. Rable, But There Was No Peace: The Role of Violence in the Politics of Reconstruction (University of Georgia Press, 1984).
7. Congressional Globe, 39th-42nd Congresses (1865-1873). Available at memory.loc.gov.
8. United States v. Cruikshank, 92 U.S. 542 (1876).
9. Plessy v. Ferguson, 163 U.S. 537 (1896).
10. C. Vann Woodward, Reunion and Reaction: The Compromise of 1877 and the End of Reconstruction (Little, Brown, 1951).
11. Xi Wang, The Trial of Democracy: Black Suffrage and Northern Republicans, 1860-1910 (University of Georgia Press, 1997).
12. Paul A. Cimbala and Randall M. Miller, eds., The Freedmen's Bureau and Reconstruction (Fordham University Press, 1999).