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  The assassination set off a rapid chain of events, as Austria-Hungary immediately blamed the Serbian government for the attack.
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  Derived from machine gun models the Hotchkiss Model 1914 was one of the most popular heavy machine guns of the war
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  It helped push the United States into entering the war on the Allied side.
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  a secret diplomatic communication issued from the German Foreign Office in January 1917 that proposed a military alliance between Germany and Mexico.
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  The Russian Revolution of 1917 was one of the most explosive political events of the 20th century
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  President Woodrow Wilson went before a joint session of Congress to request a declaration of war against Germany.
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  The Battle of Argonne Forest was part of what became known as the Meuse-Argonne Offensive, the last battle of World War I
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  Germany asked the Allies for an armistice rather than surrender
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  The Fourteen Points speech of President Woodrow Wilson was an address delivered before a joint meeting of Congress on January 8, 1918
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  World War I officially ended with the signing of the Treaty of Versailles on June 28, 1919