This article covers the history of the Conservative Party of Canada and its predecessors, the Liberal-Conservative Party, the party from 1867 to 1942, and the Progressive Conservative Party of Canada.

Predecessors

The Conservative Party is political heir to a series of right-of-centre parties that have existed in Canada, beginning with the Upper Canada Tories of the nineteenth century. John A. Macdonald and George-Étienne Cartier later founded the Liberal-Conservative Party. The party later became known simply as the Conservative Party after 1873, but the official party name essentially remained Liberal-Conservative until 1938. Like its historical predecessors and conservative parties in some other Commonwealth nations (such as the Conservative Party of the United Kingdom), members of the present-day Conservative Party of Canada are sometimes referred to as "Tories". The modern Conservative Party of Canada is also legal heir to the heritage of the historical conservative parties by virtue of assuming the assets and liabilities of the former Progressive Conservative Party upon the merger of 2003.

The first incarnations of the Conservative Party in Canada were quite different from the Conservative Party of today, especially on economic issues. The early Conservatives were known to espouse economic protectionism and British imperialism, by emphasizing Canada's ties to the United Kingdom while vigorously opposing free trade with the United States, free trade being a policy which, at the time, had support from the ranks of the Liberal Party. The Conservatives also sparred with the Liberal Party because of its connections with French Canadian nationalists including Henri Bourassa, who wanted Canada to distance itself from Britain and demanded that Canada recognize that it had two nations, English Canada and French Canada, connected together through a common history.

Progressive Conservative Party of Canada

The Conservative Party's popular support waned (particularly in Western Canada) during difficult economic times from the 1920s to 1940s, as it was seen by many in the west as an eastern establishment party that ignored the needs of the citizens of Western Canada. Westerners of multiple political convictions (including small-"c" conservatives) saw the party as being uninterested in the economically unstable Prairie regions of the west at the time; instead, Western Canadians believed the party held close ties with the business elite of Ontario and Quebec. As a result of western alienation, both the dominant Conservative and Liberal parties were challenged in the west by the rise of a number of protest parties including the Progressive Party of Canada, the Co-operative Commonwealth Federation (CCF), the Reconstruction Party of Canada and the Social Credit Party of Canada. In 1921, the Conservatives were reduced to third place in number of seats in the House of Common behind the Progressives. The premier of Manitoba and leader of the Progressive Party of Manitoba, John Bracken became leader of the Conservative Party in 1942 subject to several conditions, one of which was that the party be renamed the Progressive Conservative Party.

Meanwhile, many former supporters of the Progressive Conservative Party shifted their support to either the federal CCF or to the federal Liberals. The advancement of the provincially popular western-based conservative Social Credit Party in federal politics was stalled, in part by the strategic selection of leaders from the west by the Progressive Conservative Party. Progressive Conservative leaders such as John Diefenbaker and Joe Clark were seen by many westerners as viable challengers to the Liberals who traditionally had relied on the electorate in Quebec and Ontario for their power base. While none of the various protest parties ever succeeded in gaining significant power federally, they were damaging to the Progressive Conservative Party throughout its history, and allowed the federal Liberals to win election after election with strong urban support bases in Ontario and Quebec. This historical tendency earned the Liberals the unofficial title often given by some political pundits of being Canada's "natural governing party". Prior to 1984, Canada was seen as having a dominant-party system led by the Liberal Party while Progressive Conservative governments therefore were considered by many of these pundits as caretaker governments, doomed to fall once the collective mood of the electorate shifted and the federal Liberal Party eventually came back to power.

In 1984, the Progressive Conservative Party's electoral fortunes made a massive upturn under its new leader, Brian Mulroney, an anglophone Quebecer and former president of the Iron Ore Company of Canada, who mustered a large coalition of westerners, aggravated over the National Energy Program of the Liberal government, suburban and small-town Ontarians, and soft Quebec nationalists, who were angered over Quebec not having distinct status in the Constitution of Canada signed in 1982. This led to a huge landslide victory for the Progressive Conservative Party. Progressive Conservatives abandoned protectionism which the party had held strongly to in the past and which had aggravated westerners and businesses and fully espoused free trade with the United States and integrating Canada into a globalized economy. This was accomplished with the signing of the Canada-United States Free Trade Agreement (FTA) of 1989 and much of the key implementation process of the North American Free Trade Agreement (NAFTA), which added Mexico to the Canada-U.S. free trade zone.

Reform Party of Canada

In the late 1980s and 1990s, federal conservative politics became split by the creation of a new western-based protest party, the populist and social conservative Reform Party of Canada created by Preston Manning, the son of an Alberta Social Credit premier, Ernest Manning. It advocated deep decentralization of government power, abolition of official bilingualism and multiculturalism, democratization of the Senate of Canada, and suggested a potential return to capital punishment, and advocated significant privatization of public services. Westerners reportedly felt betrayed by the federal Progressive Conservative Party, seeing it as catering to Quebec and urban Ontario interests over theirs. In 1989, Reform made headlines in the political scene when its first member of Parliament (MP), Deborah Grey, was elected in a by-election in Alberta, which was a shock to the PCs which had almost complete electoral dominance over the province for years. Another defining event for western conservatives was when Mulroney accepted the results of an unofficial Senate "election" held in Alberta, which resulted in the appointment of a Reformer, Stanley Waters, to the Senate.

By the 1990s, Mulroney had failed to bring about Senate reform as he had promised (appointing a number of Senators in 1990). As well, social conservatives were dissatisfied with Mulroney's increasing social progressivism. Canadians in general were disenchanted with extremely high unemployment, Canada's soaring debt and deficit, a bungled implementation of the deeply unpopular Goods and Services Tax (GST) in 1991, and failed constitutional reforms of the Meech Lake and Charlottetown accords. In 1993, support for the Progressive Conservative Party collapsed, and the party's representation in the House of Commons dropped from an absolute majority of seats to only two seats. The 1993 results were the worst electoral disaster in Canadian history, and the Progressive Conservatives never fully recovered.

In 1993, federal politics became divided regionally. The Liberal Party took Ontario, the Maritimes and the territories, the separatist Bloc Québécois took Quebec, while the Reform Party took Western Canada and became the dominant conservative party in Canada. The problem of the split on the right was accentuated by Canada's single member plurality electoral system, which resulted in numerous seats being won by the Liberal Party, even when the total number of votes cast for PC and Reform Party candidates was substantially in excess of the total number of votes cast for the Liberal candidate.

Foundation and early history Merger agreement In 2003, the Canadian Alliance (formerly the Reform Party) and Progressive Conservative parties agreed to merge into the present-day Conservative Party, with the Alliance faction conceding its populist ideals and some social conservative elements.

On October 15, 2003, after closed-door meetings were held by the Canadian Alliance and Progressive Conservative Party, Stephen Harper (then the leader of the Canadian Alliance) and Peter MacKay (then the leader of the Progressive Conservatives) announced the "'Conservative Party Agreement-in-Principle", thereby merging their parties to create the new Conservative Party of Canada. After several months of talks between two teams of "emissaries", consisting of Don Mazankowski, Bill Davis and Loyola Hearn on behalf of the PCs and Ray Speaker Senator Gerry St. Germain and Scott Reid on behalf of the Alliance, the deal came to be.

On December 5, 2003, the Agreement-in-Principle was ratified by the membership of the Alliance by a margin of 96% to 4% in a national referendum conducted by postal ballot. On December 6, the PC Party held a series of regional conventions, at which delegates ratified the Agreement-in-Principle by a margin of 90% to 10%. On December 7, the new party was officially registered with Elections Canada. On March 20, 2004, Harper was elected leader.

Opposition to the merger The merger process was opposed by some elements in both parties. In the PCs in particular, the merger process resulted in organized opposition, and in a substantial number of prominent members refusing to join the new party. The opponents of the merger were not internally united as a single internal opposition movement, and they did not announce their opposition at the same moment. David Orchard argued that his written agreement with Peter MacKay, which had been signed a few months earlier at the 2003 Progressive Conservative Leadership convention, excluded any such merger. Orchard announced his opposition to the merger before negotiations with the Canadian Alliance had been completed. The basis of Orchard's crucial support for MacKay's leadership bid was MacKay's promise in writing to Orchard not merge the Alliance and PC parties. Over the course of the following year, Orchard led an unsuccessful legal challenge to the merger of the two parties.

In October and November, during the course of the PC party's process of ratifying the merger, four sitting Progressive Conservative MPs — André Bachand, John Herron, former Tory leadership candidate Scott Brison, and former prime minister Joe Clark—announced their intention not to join the new Conservative Party caucus, as did retiring PC Party president Bruck Easton. Clark and Brison argued that the party's merger with the Canadian Alliance drove it too far to the right, and away from its historical position in Canadian politics.

On January 14, 2004, former Alliance leadership candidate Keith Martin left the party, and sat temporarily as an independent. He was reelected, running as a Liberal, in the 2004 election, and again in 2006 and 2008.