World War 1 By evie_mikaela Jun 28, 1914 Assassination of Archduke Period: Jun 28, 1914 to Jan 10, 1920 World War 1 Aug 3, 1914 Fighting begins Sep 15, 1914 Trench Warfare Apr 1, 1915 New Weapons of World Nov 10, 1915 British Blockade Jan 19, 1917 Zimmerman Note Apr 16, 1917 America Joins Jan 8, 1918 Wilson's 14 Points Jun 18, 1918 Treaty of Versailles Jan 10, 1920 Laegue of Nations