he interwar years brought several interesting developments in labour politics. The first was the 1921 founding of the Communist Party of Canada (CPC) and the second was the creation of the Co-operative Commonwealth Federation (CCF) in 1932. As already noted, the CPC emerged as a potent organizing force in the early 1930s, initially through the Workers Unity League (WUL) and then the CIO. The party's skilled and committed union activists made a substantial contribution to the spread of the CIO in Canada. The CPC's critique of capitalism won it some intellectual and other professional support during the depths of the Great Depression. The CPC, though, fared less well at the ballot box, never becoming a potent political force except occasionally in civic elections.

The CCF emerged in the early 1930s, partly as an alternative to the CPC. CCF socialists declared their objective to be to "eradicate capitalism," but proposed to do so through gradual reform. Called "parliamentary socialism," this approach emphasized legislative acts and regulations to reform capitalism. This strategy reflected partly the prominence of former Independent Labor Party supporters in the new party. J.S. Woodsworth and A.A. Heaps from Winnipeg and William Irvine of Calgary, all labour Members of Parliament, helped organize the CCF. At its founding convention in Regina in 1933, the party elected Woodsworth its leader. The CCF received good support from prairie farmers, but did not initially enjoy significant electoral support from labour. Unfortunately for the labour movement, sharp and ever-deepening conflicts between the CCF and CPC over questions of ideology and political strategy divided and weakened labour's political voice.