World War I By Brittney Croker Jul 28, 1914 Start of World War I Aug 5, 1914 Canada Joins World War I Period: Sep 10, 1914 to Oct 10, 1918 Trench Warfare Apr 22, 1915 Second Battle of Ypres Jul 1, 1916 Battle of Somme Apr 9, 1917 Vimy Ridge Jul 11, 1917 Passchendaele Aug 15, 1917 Hill 70 Nov 11, 1918 End of WWI Jun 28, 1919 Treaty of Versailles