The Liberal Party of Canada (French: Parti libéral du Canada) is the longest-serving and oldest active federal political party in Canada.The party has dominated federal politics of Canada for much of its history, holding power for almost 70 years of the 20th century. As a result, it has sometimes been referred to as Canada's "natural governing party".

Party systems model. According to recent scholarship, there have been four party systems in Canada at the federal level since Confederation, each with its own distinctive pattern of social support, patronage relationships, leadership styles, and electoral strategies. Steve Patten identifies four party systems in Canada's political history. The first party system emerged from …