The horrendous combat at Antietam shook the nation, as eyewitnesses described regiments being cut down in rows. A New York Tribune correspondent wrote "the dead are lying, literally in heaps." Points on the landscape such as The Cornfield and Bloody Lane became legendary.
The battle turned back the Confederate invasion of the North, and was enough of a victory that President Lincoln felt confident in announcing the Emancipation Proclamation days later. But the political impact of the battle was always overshadowed by the sheer intensity of the fighting.
Antietam would always be remembered as the bloodiest day in American history.
Photograph: Bodies by the Dunker Church at Antietam/Photograph by Alexander Gardner, courtesy Library of Congress
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