World War I

The following notes will help you prepare for questions about World War I on the AP U.S. History Exam.

  • There was no single cause for World War I. European powers had been vying to build their empires while many in the United States wanted the U.S. to maintain its foreign policy of isolationism. President Wilson continued to say that the U.S. would not get involved in a European war, even after the assassination of Austrian Archduke Franz Ferdinand by a Serbian national. However, the Zimmerman Telegram pulled the U.S. into the war in its final stages. The first U.S. troops arrived in Europe in June 1917.

  • Complicating Wilson's decision to send troops overseas was a worldwide flu pandemic. Wilson himself contracted the illness, which infected millions. Over 650,000 Americans died of the flu between 1918 and 1919, which was more deaths than from all 20th century wars combined.


conscientious objector : someone refuses to fight in combat for religious or personal reasons

doughboys : inexperienced, young American draftees sent to Europe fight in the war

Espionage Act of 1917 : gave post offices the right to not deliver anti-war mail, made it a crime to interfere with the draft; broad bill intended to reduce the opportunities for German Americans to spy on behalf of Germany or aid Germany in the war effort

League of Nations : created with goal of ensuring war never occurred again; championed by Woodrow Wilson but the U.S. never joined

liberty bonds : used by the government to raise money for the war; considered a patriotic act to purchase a bond

Lusitania : British ship sunk by Germany on May 7, 1914; raised anti-German sentiment in the U.S. but did not directly lead to the U.S. entering the war

Sedition Act : added on to Espionage Act; made it illegal to speak out against the government or the war; criticized for being unconstitutional

Selective Service Act : draft; few Americans wanted to volunteer for the war

Treaty of Versailles : peace treaty that ended World War I; forced Germany to take the blame and indirectly led to World War II

trench warfare : warfare fought from deep trenches, with up to a mile of space in between opposing trenches

u-boat : German submarines

Zimmerman Telegram : telegram intercepted and decoded by Great Britain; Germany offered Mexico money and land previously lost to the U.S. if it sided with Germany in the war; Great Britain used this to convince the U.S. to join the war

People :

Archduke Franz Ferdinand : Heir apparent to the throne of Austria-Hungary; assassinated by a Serbian national on June 28, 1914; sparked World War I

Kaiser Wilhelm : Emperor of Germany; forced out of power after Germany's defeat in the war


Related Links:
Revolutionary War and a New Nation Quiz
AP US History Quizzes
AP US History Notes
World War I Timeline
World War I Facts
World War 1 Timeline Quiz
American Revolution
Antebellum America

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