World War 1 By artavious20001 Jun 28, 1914 Assassination of the Archduke Ferdinand Archduke Ferdinand Jul 30, 1914 Russia Mobilizes Russia Mobilizes Aug 4, 1914 Britain declares war on Germany. Britain declares war on Germany Aug 26, 1914 Battle of Tannenberg Battle of Tannenberg Period: Feb 17, 1915 to Jan 9, 1916 Gallipoli Campaign Gallipoli Campaign May 7, 1915 May 7, 1915. Lusitania Sinks Lusitania Sinks Period: Jul 1, 1916 to Nov 18, 1916 Jul 1, 1916 – Nov 18, 1916 The Battle of Somme Battle of Somme Feb 25, 1917 Feb 25, 1917 Zimmerman Telegram Zimmerman Telegram Apr 6, 1917 U.S. declares war on Germany. U.S. declares war on Germany Period: Jul 31, 1917 to Nov 10, 1917 Jul 31, 1917 – Nov 10, 1917 Battle of Passchendaele Battle of Passchendaele Period: Nov 20, 1917 to Dec 6, 1917 Battle of Cambrai Battle of Cambrai Dec 7, 1917 U.S. declares war on Austria-Hungary. U.S. declares war on Austria-Hungary Nov 11, 1918 Armistice Day Armistice Day Period: Jun 28, 1919 to Jan 21, 1920 Signing of the Treaty of Versailles Treaty of Versailles
