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  Archduke Franz Ferdinand and his wife are assassinated by Gavrilo Princip, a fanatical Serbian separatist.
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  In the wake of the assassination Austro-Hungarian emperor Franz Joseph declares war on Serbia.
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  Russia, ally of Serbia, mobilized its military in response to Austria-Hungary's declaration of war.
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  Germany's declaration of war with Belgium causes Great Britain to declare war on Germany.
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  In this offensive, which occurred east of Paris, 27,000 French troops died in one day.
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  As the war reaches a stalemate trenches begin to appear along the western front.
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  Germany announces a submarine blockade of Great Britain.
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  A German U-Boat sinks the Lusitania, killing 1, 198 civilians including 128 Americans. The sinking generated significant outrage in the United States, although the vessel was transporting munitions.
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  Lasting nearly one year, the Battle of Verdun resulted in nearly 1 million casualties.
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  The Battle of Somme lasted nearly five months and produced approximately 1 million casualties, but did not result in any significant gain for the allies. Somme saw the first employment of the tank, used by British forces but with little success.
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  Germany's unrestricted submarine warfare combined with the discovery of the Zimmerman telegram draws the United States into World War I.
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  After Lenin and the Bolsheviks overthrow Kerensky's government the new Russian leadership signs an armistace with Germany.
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  American forces halt the German advance along the banks of the Marne River.
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  Allied forces begin a series of successful counteroffensives along the Somme, forcing the Germans to retreat.
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  In a move known as the "hundred days offensive" allied forces push through the Hindenberg line, a heavily fortified zone that served as Germany's last line of defense.
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  On November 9th Kaiser Wilhelm abdicated, and on the 11th hour of November 11th World War I ended.
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  The Treaty of Versailles is signed in Paris. The severe punishments levied upon Germany set the stage for a second world war. Ironically France's surrender in World War II will be signed in the same train car in which the Treaty of Versailles was signed following World War I.