Boris Johnson may have won a no-confidence vote on Monday night, but history suggests that his political future remains precarious. Among the three other Conservative British prime ministers who faced similar votes in recent decades, two were ultimately forced out. One survived, but lost in a landslide election two years later.
Theresa May, who was prime minister from 2016 to 2019, faced a no-confidence vote in December 2018 over opposition to her Brexit agreement with the European Union. She prevailed 200 to 117 — a higher share than Mr. Johnson — but only after promising her fellow Conservatives that she would step down before the next general election.
A few months later, after repeatedly failing to get her Brexit plan through Parliament, Mrs. May said she would step down as leader of the Conservative Party and as prime minister.
More than 20 years before, John Major, Britain’s prime minister from 1990 to 1997, triggered a party leadership election in 1995 to try to quiet Conservative critics, securing 218 votes against 89 for his opposer — also a higher share than Mr. Johnson. Mr. Major continued as leader of the Conservatives and prime minister until he lost in the 1997 general election to Tony Blair’s Labour Party.
In 1989, Margaret Thatcher, who had been prime minister for 10 years and leader of the Conservative Party for 14, was challenged in a party leadership vote in part over her increasingly resistant attitude toward the European Community’s further political and economic integration and leadership style. She won a robust majority, but her popularity had been weakened — also by a highly unpopular household tax that she refused to abandon — and the next year, her leadership was put up for a vote again.
She won narrowly in a first round of voting against Michael Heseltine — 204 to 152 — but failed to achieve the 15 percent margin necessary to win outright. She decided not to stand for a second round of voting, and stepped down a few days later.
