The definitive account of the Battle of Antietam, the bloodiest day of the Civil War. The memory of the Battle of Antietam was so haunting that when, nine months later, Major Rufus Dawes learned another Antietam battle might be on the horizon, he wrote, "I hope not, I dread the thought of the place." In this definitive account, historian D. Scott Hartwig chronicles the single bloodiest day in American history, which resulted in 23,000 casualties.