Civil War, American

War (1861–65) between the Southern or Confederate States of America (see Confederacy) and the Northern or Union states. The former wished to maintain certain ‘states' rights’, in particular the right to determine state law on the institution of slavery, and claimed the right to secede from the Union; the latter fought primarily to maintain the Union, with slave emancipation (proclaimed in 1863) a secondary issue.

The issue of slavery had brought to a head long-standing social and economic differences between the two oldest sections of the country. A series of political crises was caused by the task of determining whether newly admitted states, such as California, should permit or prohibit slavery in their state constitutions; the resulting Compromise of 1850 made various concessions to the slave states. The political parties in the late 1850s came to represent only sectional interests – Democrats in the South, Republicans in the North. In the presidential campaign of 1860, the Democrats divided among themselves, while the Republicans nominated Abraham Lincoln on an antislavery platform that denied the right of Congress to give legality to slavery in any territory. Lincoln swept the North, but the threats of secession made by southern orators for 40 years were soon realized. The breakdown of an underlying national political consensus (which had previously sustained national parties) led to the outbreak of hostilities, only a few weeks after Lincoln's inauguration.

The war, and in particular its aftermath, when the South was occupied by northern troops in the period known as Reconstruction, left behind much bitterness. Industry prospered in the North, while the economy of the South, which had been based on slavery, stagnated for some time.