Eamon de Valera publicly repudiated the Anglo-Irish Treaty.
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The Commonwealth of Independent States was formed by the leaders of Russia, Ukraine, and Belarus.
Dwight D. Eisenhower gave his 'Atoms for Peace' speech at the United Nations in New York.
SpaceX became the first private company to launch, orbit, and recover a spacecraft.
Metallica became the first band to have performed on all seven continents when they held a concert in Antarctica.
Abraham Lincoln issued his Amnesty Proclamation and plan for the Reconstruction of the South.
