When Prime Minister Robert Borden returned from a series of meetings with the Imperial Staff in the spring of 1917, he was convinced that conscription (compulsory military enlistment) was needed in order to maintain the strength of the Canadian Corps in France. Voluntary enlistment had dropped off sharply. At the beginning of 1916, the average rate of enlistment was 30,000 a month, but this figure had declined to 6,000 a month by the end of the year. Borden felt that compulsory service was necessary for Canada to maintain its commitment to the war in Europe.
Conscription was a politically divisive issue. Resistance was strongest in Quebec, where a majority had opposed Canada's involvement in a "European" war, but such reservations were not limited to the French-Canadian population. Organized labour bitterly opposed compulsory enlistment, fearing that it would lead to the conscription of workers for war industries. Many farmers were concerned that compulsory enlistment would create a shortage of agricultural labour at a time when they were hard pressed to meet the demands of wartime consumption. Consequently, conscription-which the Borden government had introduced with the passage of the Military Service Act in August 1917-became the dominant issue in the December 1917 federal election.
Prior to the election, the Borden government passed the Military Voters Act and the Wartime Elections Act. The Military Voters Act gave the right to vote to all military personnel regardless of gender and contained provisions that would allow them to assign their vote to any constituency in Canada. The Wartime Elections Act extended the franchise to all wives, mothers, sisters, and daughters of servicemen and, at the same time, disenfranchised many voters of enemy-alien birth who had immigrated to Canada after 1902. These two pieces of legislation increased the number of voters most likely to support conscription and eliminated ones unlikely to support compulsory service.
Borden led the Union government, a coalition of Conservatives and pro-conscription Liberals. Borden won the election, but the country was divided as never before. English-Canada voted overwhelmingly to support the Union government, while Quebec supported Laurier and the Liberals who refused to support conscription.