Answer: June 28, 1914 = Archduke Francis Ferdinand is assassinated by a Slavic nationalist (catalyst)
July 28, 1914 = Austria-Hungary declares war on Serbia
May 7, 1915 = German U-boat sinks the British ship Lusitania with American passengers on board. The American public is outraged
July 1, 1916 = Allied offensive begins the Battle of the Somme against the central powers
February 3, 1917 = United States severs diplomatic relations with Germany after they break international law of the seas.
April 6, 1917 = Us declares war on Germany, breaking neutrality
November 8, 1917 = Lenin takes over Russia (Bolshevisk)
January 8, 1918 = President Wilson presents to Congress his outline of Fourteen Points.
March 3, 1918 = Russia signs the Treaty of Brest-Litovsk with Germany, letting go of many Russian lands like Poland.
November 11, 1918 = Germany signs the Armistice at Compiègne, ending World War I.
January 18, 1919 = Peace conference begins at Paris.
February 14, 1919 = Draft of the League of Nations is completed.