The American Civil War was a conflict fought in the United States from 1861 to 1865. It primarily arose from tensions between the Northern states, known as the Union, and the Southern states, known as the Confederacy. Key issues included slavery, states' rights, and economic differences. The war resulted in significant loss of life and widespread destruction. The war began with the Battle of Fort Sumter and included major battles such as the Battle of Gettysburg and the Battle of Antietam. It ended with the surrender of General Robert E. Lee at Appomattox Court House. The conflict ultimately led to the abolition of slavery in the United States.