American Civil War: The Battle of Wauhatchie, one of the few night battles of the war, concluded with the Union Army opening a supply line to troops in Chattanooga, Tennessee.

The American Civil War was a civil war in the United States between the Union and the Confederacy, which formed in 1861 by Southern states that had decided to secede from the Union to preserve slavery in the United States. The South saw slavery as threatened because of the election of Abraham Lincoln as president in 1860 and the growing abolitionist movement in the North. The war ended with a Union victory, dissolution of the Confederate States and the national abolition of slavery, freeing four million African Americans.