The document summarizes the Pulitzer Prize-winning novel "The Killer Angels" by Michael Shaara about the three-day Battle of Gettysburg during the American Civil War. It describes the main characters, including Confederate General Robert E. Lee and Union Colonel Joshua Chamberlain, and outlines the events of the battle from June 30 to July 3, 1863. On the last day, the failed Pickett's Charge by Confederate General George Pickett effectively ended the battle, and Lee's army was forced to retreat, dealing a major blow to the Confederacy.