For 10 points, name this 1862 battle that was the bloodiest single day of combat during the Civil War.
During this battle, Joseph Mansfield led his forces up near the Dunker Church. John Sedgwick's troops in this battle took heavy casualties after advancing from the West Woods. William French moved his forces in this battle to a sunken road that became known afterwards as the "Bloody Lane." This strategic victory for George McClellan ended Robert E. Lee's attempt to bring the Civil War into the northern states through Maryland. For 10 points, name this 1862 battle that was the bloodiest single day of combat during the Civil War.
During this battle, Joseph Mansfield led his forces up near the Dunker Church.
Battle of {Antietam} [or Battle of {Sharpsburg}]