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  William Mckinley was the president at the turn of the century, his term ended early due to his death of assassination.
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  Theodore Roosevelt was the 26th president. He took over after the death of William Mckinley and he served two terms.
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  William Taft was the 27th president, he also was the chief justice of the supreme court.
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  Theodore Roosevelt was the first president to win a Nobel Peace Prize. He was awarded the prize for his efforts in the Treaty of Portsmouth, which ended the Russo-Japanese war.
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  The 16th Amendment was ratified, it authorized income tax.
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  Woodrow Wilson was the 28th president, he was president when the U.S. entered World War I
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  The 17th Amendment was ratified, it provided direct elections for senators.
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  The global war began, however, the U.S. was not apart of it until 1917.
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  A German torpedo sunk the British passenger ship called Lusitania caused many deaths including Americans. This event was a factor in considering America's place in WW1.
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  The global war had been going on for about three years before the United States entered.
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  The 18th amendment was ratified, it prohibited alcoholic beverages.
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  The Treaty of Versailles brought World War I to an end. The Treaty gave deserved punishment to Germany.