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On This Day
America250
— 250 years since 1776. Explore two and a half centuries of American history.
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Anniversaries in American history that fall on April 12.
1955 · Technology
Salk Polio Vaccine
The 1955 vaccine that ended summer polio epidemics — and the doctor who refused to patent it
Salk Polio Vaccine
1864 · Events / Wars & Conflicts
Fort Pillow Massacre
The Confederate Slaughter of Black Union Soldiers, April 12, 1864
Fort Pillow Massacre
1861 · Eras
Confederate guns fire on Fort Sumter
War begins; Union garrison surrenders after 34-hour bombardment
The Civil War
1861 · Events / Wars & Conflicts
American Civil War
The 1861–1865 war over slavery and union that remade the nation
American Civil War