World War I, also known as the Great War, was a global conflict from 1914 to 1918 between the Central Powers of Austria-Hungary, Germany, Turkey, and Bulgaria and the Allied Powers, principally Great Britain, France, Russia, Serbia, Japan, and Italy. After trying to remain neutral for the first three years, the United States joined the Allies in 1917 mainly because of violations of America's maritime rights. The war began after the assassination of Archduke Francis Ferdinand of Austria-Hungary by a Serbian nationalist on June 28, 1914, and the great European powers' hostile alliances quickly turned that local incident into a wider war. President Woodrow Wilson urged Americans to remain neutral, but British blockade policies and German submarine warfare made neutrality difficult. Germany's submarine blockade around Britain, the sinking of the Lusitania with 128 Americans aboard, the resumption of submarine warfare in 1917 that sank four American merchant ships, the Zimmerman telegram proposing an alliance between Germany and Mexico, and Russia's replacement of tsarist rule with a representative government all helped lead Wilson to ask Congress for a declaration of war, which it issued on April 6, 1917. The U.S. military was initially unprepared, and it took nearly a year for large numbers of American soldiers, known as doughboys, to reach the western front in France. In 1918, as Germany made a final major push and came within fifty miles of Paris, American troops under French Marshal Ferdinand Foch helped stop the Germans at Château-Thierry and in the Second Battle of the Marne, then joined a successful Allied counteroffensive. In September 1918, General John “Black Jack” Pershing led American troops in the battles at St. Mihiel and in the Meuse-Argonne offensive, both successful despite heavy American casualties. Germany sought peace because of Allied successes on the western front, the continuing British blockade and food shortages in Germany, and the prospect of a continuing flow of American troops. An armistice ended the fighting on the eleventh hour of the eleventh day of the eleventh month of 1918. The Treaty of Versailles, signed on June 28, 1919, placed harsh terms on Germany, including responsibility for the war and reparations. Wilson accepted the treaty because it included the League of Nations, but the U.S. Congress did not ratify it, and the United States never joined the League. Many historians have argued that the treaty's harshness and the United States' refusal to join the League of Nations were among the main causes of World War II, as Adolf Hitler later used German resentment to unite and rearm Germany in the 1930s while America's absence from the League left it unable to stop his treaty violations.