American Civil War: Future U.S. president Ulysses S. Grant engaged in his first combat leadership role in the Battle of Belmont in Mississippi County, Missouri.

The American Civil War was a civil war in the United States between the Union and the Confederacy, which was formed in 1861 by Southern 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 as president in 1860 and the growing abolitionist movement in the North. The war ended with a Union victory, dissolution of the Confederacy and the national abolition of slavery, freeing four million African Americans.