The Battle of Antietam remains the bloodiest day in American history with over 23,000 casualties. The battle results when confederate General Lee invades Maryland hoping to inflict a decisive defeat on the union army. But union General McClellan obtains a copy of Lee's plans and has the opportunity to crush Lee's army while it is widely dispersed. The two armies meet outside the town of Sharpsburg, Maryland on September 17, 1862.

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