The Battle of Antietam
The Battle of Antietam, also called the Battle of Sharpsburg, occurred on September 17, 1862, at Antietam Creek near Sharpsburg, Maryland. It pitted Confederate General Robert E. Lee’s Army of Northern Virginia against Union General George McClellan’s Army of the Potomac and was the culmination of Lee’s attempt to invade the north. The battle’s outcome would be vital to shaping America’s future, and it remains the deadliest one-day battle in all of American military history.
Do you have the options? If not I'd say European Imperialism was started by Portugal.
