Two parties have dominated politics in Canada: the
Liberal party and the
historic Conservative party (known as the
Progressive Conservative party from 1943). If one regards the
modern Conservative party as the successor to the historic one, then these are the only two parties to have formed a government. (The 1917 win was by a pro-conscription
Unionist coalition, between former Liberals and Conservatives).
Although government has been a
two-party system, Canadian federal politics has been a
multi-party affair since the 1920s, which saw significant parliamentary presence from the
Progressive party and the
United Farmers movement. They were supplanted by the
Social Credit party and the
Co-operative Commonwealth Federation (CCF) in the 1930s. The CCF evolved into the
New Democratic Party (NDP) in 1961. The Social Credit party and the CCF/NDP occupied the 3rd and 4th party slots between them from the 1930s, until the Social Credit party failed to win any seats in the 1980 election.
Since 1980, the NDP have remained a presence in the Canadian parliament, but the situation amongst other non-government parties has been more complex. The historic Conservative party never recovered from its spectacular defeat in the 1993 election (when it went from being the majority government with 169 seats, to just two seats and the loss of official party status). Right-wing politics has since seen the rise and fall of the
Reform party and the
Canadian Alliance, followed by the rise to government of the new
Conservative party. Further, 1993 saw the first seats won by the separatist
Bloc Québécois, who have been a constant presence in the Canadian parliament since then