American Civil War: United States President Abraham Lincoln reluctantly restores Union General George B. McClellan to full command after General John Pope's disastrous defeat at the Second Battle of Bull Run.

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…