sland (which had been united in 1866) joined the Confederation in 1871, while Prince Edward Island joined in 1873. Prime Minister John A. Macdonald and his Conservative government established a National Policy of tariffs to protect the nascent Canadian manufacturing industries.
To open the West, the government sponsored the construction of three transcontinental railways (including the Canadian Pacific Railway), opened the prairies to settlement with the Dominion Lands Act, and established the North-West Mounted Police to assert its authority over this territory. In 1898, during the Klondike Gold Rush in the Northwest Territories, the Canadian government created the Yukon Territory. Under the Liberal Prime Minister Wilfrid Laurier, continental European immigrants settled the prairies, and Alberta and Saskatchewan became provinces in 1905.
Early 20th century
Because Britain still maintained control of Canada's foreign affairs under the Confederation Act, its declaration of war in 1914 automatically brought Canada into World War I. Volunteers sent to the Western Front later became part of the Canadian Corps. The Corps played a substantial role in the Battle of Vimy Ridge and other major engagements of the war. Out of approximately 625,000 Canadians who served in World War I, around 60,000 were killed and another 173,000 were wounded. The Conscription Crisis of 1917 erupted when conservative Prime Minister Robert Borden brought in compulsory military service over the objections of French-speaking Québécois. In 1919, Canada joined the League of Nations independently of Britain, and the 1931 Statute of Westminster affirmed Canada's independence.
The Great Depression of the early 1930s brought great economic hardship to Canada. In response to the downturn, the Co-operative Commonwealth Federation (CCF) in Saskatchewan introduced many elements of a welfare state (as pioneered by Tommy Douglas) in the 1940s and 1950s. Canada declared