American Civil War: Confederates commanded by Brig. Gen. John B. Floyd attack General Ulysses S. Grant's Union forces besieging Fort Donelson in Tennessee. Unable to break the fort's encirclement, the Confederates surrender the following day.

The American Civil War was a civil war in the United States between the Union and the Confederacy, which was formed in 1861 by states that had seceded from the Union to preserve slavery in the United States. The South saw slavery as threatened because of the election of Abraham Lincoln and the…