Causes & Consequences of WW1 By CurrenJackson Period: 1900 to 1950 WW1 Period: 1904 to 1905 Russo-Japanese War Period: 1914 to 1919 WW1 Jul 28, 1914 Austria-Hungary declared war on Serbia Aug 14, 1914 Japan Declared War on Germany Aug 23, 1914 Japan declared war on Germany 1915 Italy joined the allies 1915 Germans began to use poison gas/tear gas Period: 1915 to 1917 Armenian Genocide 1917 Russia withdrew from the war 1917 Airplanes started being used to drop artillary Apr 6, 1917 United States enters war 1918 Wilson's 14 points 1918 Second battle of the Somme Nov 11, 1918 War was ended Nov 11, 1918 Germany signs armistice