World War I: A global conflict that took place primarily in Europe from 1914-1918. The U.S. entered the war in 1917 on the side of the Allies (including Britain and France) against the Central Powers (including Germany).
Propaganda: Information, especially biased or misleading nature, used to promote a political cause or point of view. During WWI and WWII, propaganda was used extensively to fuel anti-German sentiment.
Xenophobia: Dislike or prejudice against people from other countries. Anti-German sentiment is an example of xenophobia.