World War I or the "Great War" was supposed to be the "war to end all wars." It was fought from 1914-1918, mainly in western and eastern Europe. The Allies included the United States (joined 1917), Great Britain, France, Italy, Japan, and Russia. The Central Powers included Germany, Austria-Hungary, and the Ottoman Empire. World War I saw the first large scale use of airplanes and tanks. The fighting stopped with an armistice on the 11th hour of the 11th day of the 11th month (11 November 1918) and formally ended with the Treaty of Versailles in 1919 (never ratified by US Senate).