Description: The American Civil War, from 1861 to 1865 was a civil war in the United States between the Union or the North and the Confederacy or the South, which was formed in 1861 by states that had seceded from the Union. Battles such as the First Bull Run, Antietam, Vicksburg, Shiloh and Gettysburg were some of the most important battle of the US Civil War.