The Causes and Consequences of WWI By deumdd Period: 1870 to 1920 WWI Events Events leading up to WWI and consequences 1871 Germany Became Unified Nation 1871 Germany Surpassed Britain 1878 Serbia's Independence 1901 Japan & Russia Went to War over Manchuria 1904 Russian Japanese War 1907 British Joined Triple Allies 1910 Manchuria Went Back to China 1914 Austria Declared War onto Serbia 1914 WWI 1914 Japan Wanted War with Germany Aug 23, 1914 Japan Declared War on Germans 1915 Britain's Passenger Ship Went Down 1915 Italy Joined Allies 1917 US Entered War 1917 Airplanes were Used for War 1917 Russia Had to Withdraw from the War 1917 Russia Had to Withdraw from the War Apr 4, 1917 US Entered War Nov 11, 1918 Last Day of War