Episode 12: 1915 to 1929 CE. Canada's heavy military role in World War I (60,000 dead in a population of eight million) transforms its society, its politics and its place in the world. The horror, bravery and sacrifice of trench warfare are evoked in Canada's great battles: Ypres, the Somme, Vimy Ridge, Courcelette and Passchendaele. The domestic consequences of Canada's war effort are also wrenching — the conscription crisis of 1917 marks a low point in English-French relations. After the war ends, labour revolts in Winnipeg and across the country raise fears of a Bolshevik insurrection. The return to stability in the mid-1920s lasts only briefly, as the crash of 1929 plunges the country into economic chaos.