What Was the Deadliest Day in American History?

When dark days in U.S. history are recalled, they usually include Pearl Harbor and the September 11 terrorist attacks, both of which killed about 3,000 people.

But the single bloodiest day in American military history occurred on this date in 1862, in the battle of Antietam, near Sharpsburg, Maryland.

Forces of Union General George McClellan and the Confederate troops of General Robert E. Lee met in a daylong pitched battle. By its end, more than 23,000 soldiers had been killed or wounded. During the Civil War, 140,000 Union soldiers alone were killed in battle. This is almost half the U.S. battle deaths during World War II, when the armed forces were eight times as large.

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