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  The summer Olympics of the II Olympiad were held in Paris, France. it was the first Olympics where women are allowed to compete. opening day was May 14,1900.
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  McKinley had his second inauguration.
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  The Wright brothers make the first sustained flight in an aircraft at Kitty Hawk, N.C.
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  Theodore Roosevelt was inaugurated for a second time.
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  An earthquake in San Francisco leaves 500 dead or missing and destroys about 4 square miles of the city.
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  William Taft is inaugurated as the 27th president.
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  The U.S. enters World War I, declaring war on Germany. The cause for this was the sinking of the ship Lusitania which was sunk by a German U-Boat.
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  The Senate refuses to ratify the Versailles Treaty or authorize United States participation in the League of Nations.