Third Thatcher ministry to make way for a leader more likely to win the next general election. Her successor was the Chancellor of the Exchequer John Major, who was elected on 27 November 1990, and who at 47 became the youngest Conservative Prime Minister of the 20th century. <section begin="June 1987 to July 1989" /> <section begin="July 1989 to November 1990" /> Members of the Cabinet are in bold face. Third Thatcher ministry Margaret Thatcher was Prime Minister of the United Kingdom from 4 May 1979 to 28 November 1990, during which time she led a Conservative government. She was the first woman
Premiership of Margaret Thatcher Meyer. As Meyer was a virtually unknown backbench MP, he was viewed as a "stalking horse" candidate for more prominent members of the party. Thatcher easily defeated Meyer's challenge, but there were sixty ballot papers either cast for Meyer or abstaining, a surprisingly large number for a sitting Prime Minister. Her supporters in the Party, however, viewed the results as a success, claiming that after ten years as Prime Minister and with approximately 370 Conservative MPs voting, the opposition was surprisingly small. Thatcher was fiercely committed to a new tax—commonly called the "poll tax"—that would apply in equal amounts to