When Germany torpedoes a British passenger ship believed to be smuggling arms, anger at the resulting American deaths increases pressure on President Wilson to enter World War I.

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After two years of trench warfare, the Allies attempt to break through German lines on the Western Front. The ensuing battle will last for months and result in more than one million casualties.

James Watson Gerard, American ambassador to Germany during World War I, gives a notorious speech to the Ladies Aid Society of St. Mary's Hospital in New York in November 1917, calling for German Americans to be loyal to the United States or risk being shipped back to the Fatherland.

Samuel Gompers, founder of the American Federation of Labor (AFL), discusses the effects of World War I on the United States.

German resentment over harsh peace terms leads to a rise in nationalist sentiment and the eventual rise to power of Adolf Hitler.

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King George V speaks to the crowds gathered in London to celebrate his Silver Jubilee on May 6, 1935.