The American Civil War, widely known in the United States as simply the Civil War as well as other sectional names, was fought from 1861 to 1865. Seven Southern slave states individually declared their secession from the United States and formed the Confederate States of America, known as the "Confederacy" or the "South". They grew to include eleven states, and although they claimed thirteen states and additional western territories, the Confederacy was never recognized by a foreign country. The states that did not declare secession were known as the "Union" or the "North". The war had its origin in the fractious issue of slavery, especially the extension of slavery into the western territories. After four years of bloody combat that left over 600,000 Union and Confederate soldiers dead, and destroyed much of the South's infrastructure, the Confederacy collapsed, slavery was abolished, and the difficult Reconstruction process of restoring national unity and guaranteeing civil rights to the freed slaves began.
In the 1860 presidential election, Republicans, led by Abraham Lincoln, opposed the expansion of slavery into US territories. Lincoln won, but before his inauguration on March 4, 1861, seven slave states with cotton-based economies formed the Confederacy. The first six to secede had the highest proportions of slaves in their populations, a total of 48.8% for the six. Outgoing Democratic President James Buchanan and the incoming Republicans rejected secession as illegal. Lincoln's inaugural address declared his administration would not initiate civil war. Eight remaining slave states continued to reject calls for secession. Confederate forces seized numerous federal forts within territory claimed by the Confederacy. A peace conference failed to find a compromise, and both sides prepared for war. The Confederates assumed that European countries were so dependent on "King Cotton" that they would intervene; none did and none recognized the new Confederate...