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  Austria/Hungary declares war on Serbia
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  President Woodrow Wilson announces the US will remain neutral
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  Germany declares an area around Great Britain as a "war zone"
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  British ocean liner RMS Lusitania is sunk by German U-Boat
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  Battle of Somme begins, tanks are introduced
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  Battle of Verdun begins, which was the bloodiest and longest battle
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  Major naval battle, Battle of Jutland, begins
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  Bolsheviks overthrow Russian government
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  Woodrow Wilson issues his fourteen points to peace
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  Germany launches the Spring Offensive
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  A nationwide fear of communists, socialists, anarchists, and other dissidents suddenly grabbed the American psyche
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  The Enabling Legislation for the Eighteenth Amendment which established prohibition in the United States
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  Prohibits each state and the federal government from denying any citizen the right to vote based on the citizen's gender.
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  Two men believed to be murderers, much evidence was shown against them. After six years of seperation, the two men were brought together and their executions were scheduled for April.
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  Smoot-Hawley Tariff is signed by president Herbert Hoover
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  President Herbert Hoover asks congress to pass a bill for $150 million for a public works project to combat the depression
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  Star-Spangled Banner is approved as the nation's national anthem
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  Empire State Building is completed and opened for business
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  The highest continuous paved road in the United States, the Trail Ridge Road in Rocky Mountain National Park, Colorado, is opened to traffic
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  Franklin D. Roosevelt is inaugurated for the first time
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  America declares war on Germany
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  The 21st Amendment to the U.S. Constitution is passed, ending prohibition
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  The U.S. Securities and Exchange Commission is established with the signing of the Securities Exchange Act into law by President Franklin D. Roosevelt
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  Hoover Dam is dedicated by President Roosevelt
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  The U.S. government issues its first Social Security checks, totaling just over $75,000
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  Italy declares war on Britain and France, and U.S. President Roosevelt announces a shift from neutrality to "non-belligerency," meaning more active support for the Allies against the Axis
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  First East European Communist government set up in Albania
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  Communists seize power in Poland. Truman Doctrine is announced
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  The Berlin Airlift begins
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  North Atlantic Treaty Organization (NATO) established
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  U.S. and other U.N. members fight North Korean forces
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  U.S. sponsored coup overthrows Iranian government
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  Warsaw Pact was formed
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  Red Army crushes the Hungarian Revolution
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  Soviets launch first man‑made satellite
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  Fidel Castro becomes premier of Cuba, installs Communist government