1. It was a global war
Over 30 nations declared war between 1914 and 1918. The majority joined on the side of the Allies, including Serbia, Russia, France, Britain, Italy and the United States. They were opposed by Germany, Austria-Hungary, Bulgaria and the Ottoman Empire, who together formed the Central Powers. What began as a relatively small conflict in southeast Europe became a war between European empires. Britain and its Empire’s entry into the war made this a truly global conflict fought on a geographical scale never seen before. Fighting occurred not only on the Western Front, but in eastern and southeast Europe, Africa and the Middle East.