On August 4, 1914, Britain entered the First World War (1914–1918) by declaring war on Germany. The British declaration of war automatically brought Canada into the war, because of Canada's legal status as subservient to Britain. However, the Canadian government had the freedom to determine the country's level of involvement in the war. The Militia was not mobilized and instead an independent Canadian Expeditionary Force was raised. The highpoints of Canadian military achievement during the First World War came during the Somme, Vimy, and Passchendaele battles and what later became known as "Canada's Hundred Days".