During World War I, Germany offered Mexico the return of its lost territories of Texas, Arizona, and New Mexico if it attacked the United States

World War I ended at eleven o'clock on 11/11/18: the eleventh day of the eleventh month

The use of chemical weapons including chlorine and mustard gas resulted in over 1.2 million casualties

In the aftermath of the war, four empires disappeared: the German, Austro-Hungarian, Ottoman, and Russian and numerous nations regained their former independence

During World War I, about one third of military deaths were caused by the Spanish Flu

Over 9 million soldiers and 7 million civilians died during World War I