was personally defeated in Portage la Prairie, with his party nationally falling to third place behind the newly formed Progressive Party.

Opposition, 1921–1926
Meighen continued to lead the Conservative Party (which reverted to its traditional name), and was returned to Parliament in 1922, after winning a by-election in the eastern Ontario riding of Grenville.

Despite his party finishing in third place, Meighen became Leader of the Opposition after the Progressives declined the opportunity to become the Official Opposition. Unlike the situation with Laurier and Borden, who had a generally respectful personal relationship despite their clear ideological differences, there existed between Meighen and King a very deep personal distrust and animosity. Meighen looked down upon King, whom he called "Rex" (King's old University nickname), and considered him unprincipled. King viewed Meighen asfrom the upper house in January 1942.

Second Conservative leadership
In late 1941, Meighen was prevailed upon by a unanimous vote in a national conference of the party to become leader of the Conservative Party for the duration of the war. He accepted the party leadership on 13 November 1941, foregoing a leadership convention, and campaigned in favour of overseas conscription, a measure which his predecessor, Robert Manion, had opposed. As leader, Meighen continued to champion a National Government including all parties, which the party had advocated in the 1940 federal election.

Meighen, lacking a Commons seat, resigned from the Senate on 16 January 1942, and campaigned in a by-election for the Toronto riding of York South. His candidacy received the improbable support of the Liberal Premier of Ontario Mitchell Hepburn;