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  Archduke Francis Ferdinand was assassinated by Gavrilo Princip on Vitus Day.
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  Austria demanded Serbia to end all anti-Austrian activities and to let Austria officials handle the investigation of the assassination of Francis Ferdinand.
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  Austria-Hungary declared war on Serbia.
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  German troops crossed the border into Belgium, causing the first battle in the war.
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  A German U-boat sunk the British Ocean Liner Lusitania with torpedoes.
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  Italy declared war on Germany and Austria.
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  German troops were attacked by British forces in Loos, Belgium.
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  U.S. president Woodrow Wilson found out that Germany sent a telegram to Mexico proposing that they make an alliance against the U.S.
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  The first 14,000 U.S. infantry troops landed in France to join the war.
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  The Treaty of Versailles was signed and the war ended.