The Canadian federal election of 1925 was held on October 29 to elect members of the Canadian House of Commons of the 15th Parliament of Canada. Prime Minister William Lyon Mackenzie King's Liberal Party formed a minority government. This precipitated the "King-Byng Affair".
The Liberals under Mackenzie King won fewer seats than Arthur Meighen's Conservatives. A third party, the Progressives, which had nominated candidates for the first time in the 1921 election, held the balance of the seats. King decided to hold onto power with the help of the Progressives. The Progressives were closely aligned with the Liberals, and enabled King to form a minority government.
This plan was complicated by the fact that his party lost the election, and that King himself had lost his seat in the House of Commons. Meighen was outraged by King's move, and demanded that King resign from the Prime Minister's office. King asked a Liberal Member of Parliament for Prince Albert, Saskatchewan to resign so that he could run in the resulting by-election. Prince Albert was one of the safest seats in Canada for the Liberals, and King won easily.
An interesting side-note is that his Conservative opponent was John Diefenbaker. While Diefenbaker stood no chance against King in 1925, he would later win both the riding of Prince Albert and the Prime Minister's office.
With King back in Parliament, a huge scandal rocked the King cabinet when one of his appointees was discovered to be accepting bribes. Anticipating a defeat in the Commons, King asked the Governor General, Baron Byng of Vimy, to call an election. The Governor General refused, and King resigned.
King was not a crusader, or a polemicist, or a debater, but he saw this as interference in Canadian politics by an official appointed by a foreign power. King showed rare fire, and rallied the Progressives back into his camp. He defeated Meighen on a vote of confidence after only a few months. This time, Byng called an election.
King formed a majority government as a result of the 1926 election. After his defeat, Meighen resigned as Conservative leader.

National results
Notes:
* not applicable - the party was not recognized in the previous election