<P> The American Civil War (also known by other names) was fought in the United States from 1861 to 1865 . As a result of the long - standing controversy over slavery, war broke out in April 1861, when Confederate forces attacked Fort Sumter in South Carolina, shortly after U.S. President Abraham Lincoln was inaugurated . The nationalists of the Union proclaimed loyalty to the U.S. Constitution . They faced secessionists of the Confederate States, who advocated for states' rights to expand slavery . </P> <P> Among the 34 U.S. states in February 1861, seven Southern slave states individually declared their secession from the U.S. to form the Confederate States of America, or the South . The Confederacy grew to include eleven slave states . The Confederacy was never diplomatically recognized by the United States government, nor was it recognized by any foreign country (although the United Kingdom and France granted it belligerent status). The states that remained loyal to the U.S. (including the border states where slavery was legal) were known as the Union or the North . </P> <P> The Union and Confederacy quickly raised volunteer and conscription armies that fought mostly in the South over four years . The Union finally won the war when General Robert E. Lee surrendered to General Ulysses S. Grant at the Battle of Appomattox Court House, followed by a series of surrenders by Confederate generals throughout the southern states . Four years of intense combat left 620,000 to 750,000 people dead, more than the number of U.S. military deaths in all other wars combined (at least until approximately the Vietnam War). Much of the South's infrastructure was destroyed, especially the transportation systems, railroads, mills, and houses . The Confederacy collapsed, slavery was abolished, and 4 million slaves were freed . The Reconstruction Era (1863--1877) overlapped and followed the war, with the process of restoring national unity, strengthening the national government, and granting civil rights to freed slaves throughout the country . The Civil War is the most studied and written about episode in U.S. history . </P> <P> In the 1860 presidential election, Republicans, led by Abraham Lincoln, supported banning slavery in all the U.S. territories . The Southern states viewed this as a violation of their constitutional rights and as the first step in a grander Republican plan to eventually abolish slavery . The three pro-Union candidates together received an overwhelming 82% majority of the votes cast nationally: Republican Lincoln's votes centered in the north, Democrat Stephen A. Douglas' votes were distributed nationally and Constitutional Unionist John Bell's votes centered in Tennessee, Kentucky, and Virginia . The Republican Party, dominant in the North, secured a plurality of the popular votes and a majority of the electoral votes nationally, so Lincoln was constitutionally elected president . He was the first Republican Party candidate to win the presidency . However, before his inauguration, seven slave states with cotton - based economies declared secession and formed the Confederacy . The first six to declare secession had the highest proportions of slaves in their populations, a total of 49 percent . The first seven with state legislatures to resolve for secession included split majorities for unionists Douglas and Bell in Georgia with 51% and Louisiana with 55% . Alabama had voted 46% for those unionists, Mississippi with 40%, Florida with 38%, Texas with 25%, and South Carolina cast Electoral College votes without a popular vote for president . Of these, only Texas held a referendum on secession . </P>

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