The Confederate attack was repulsed with heavy losses and no gains. McClellan continued the retreat to Harrison's Landing the next day. Lee had saved Richmond at great cost, but a new army was forming in Northern Virginia. Lee shifted his forces north and struck again at Second Manassas . Vincent Esposito makes masterly use of maps to explain the strategy behind the Civil War and other conflicts of the era.
Strategy leading up to battle and the battles themselves are well covered.
In addition to the Civil War, the sections on the Mexican War and Spanish-American War are excellent. These are better maps than those on the West Point website which were simplified to fit a shorter curriculum.