A timeline of important events in WWI

1914 June Archduke Franz Ferdinand is assassinated by a Serbian nationalist
July Austria-Hungary declares war on SerbiaRussia mobilizes its troops to defend Serbia
August Germany declares war on RussiaGermany declares war on France and invades BelgiumWWI breaks out when Britain declares war on GermanyJapan joins the Allies
 November Turkey joins Germany and Austria-Hungry
 1915  February Germany beings unrestricted submarine warfare
 May Italy joins the Allies
 1916 The Arabs revolt against their Turkish overlordsWoodrow Wilson is re-elected U.S. President
 1917  January The Bolshevik Communists come to power in Russia after overthrowing the government of the czar
 April The United States declares war on Germany
 June The first U.S troops arrive in Paris, France, on June 13
 1918  January Woodrow Wilson announces his 14 Points
 March Russia and Germany sign the Treat of Brest-Litovsk
 October Germany asks President Wilson to begin peace negotiations;Wilson rejects Germany’s request for peace talksThe U.S. Army begins its final advance on November 1
 November Germany requests an armistice on November 6Kaiser Wilhelm II abdicates on November 9;Germans revolt and take over government

Germany sings the armistice on November 11, which ends WWI

 1919 The countries that ratify the Treaty of Versailles on June 28 become the original members of the League of NationsThe U.S. Senate rejects the Treaty