Above: Map of Europe during World War I (click map to enlarge) The United States did not enter World War I until April 1917, although the conflict had begun in August 1914. After an intense period of military buildup and imperial competition, war broke out in Europe between Germany and Austria-Hungary (the Central Powers) and Britain, France, and Russia (the Allies). Turkey quickly joined the Central Powers and Italy joined the Allies in 1915. Above: Picture of German U-Boats moored in the ... Read More