Margaret Thatcher Margaret Thatcher Margaret Hilda Thatcher, Baroness Thatcher, (; 13 October 19258 April 2013) was a British stateswoman who served as Prime Minister of the United Kingdom from 1979 to 1990 and Leader of the Conservative Party from 1975 to 1990. She was the longest-serving British prime minister of the 20th century and the first woman to hold that office. A Soviet journalist dubbed her "The 'Iron Lady, a nickname that became associated with her uncompromising politics and leadership style. As Prime Minister, she implemented policies known as Thatcherism. A research chemist at Somerville College, Oxford, before becoming a barrister, Thatcher
Prime Minister of the United Kingdom conventions of the constitution. Many of the Prime Minister's executive and legislative powers are actually royal prerogatives which are still formally vested in the Sovereign, who remains the head of state. Despite its growing dominance in the constitutional hierarchy, the Premiership was given little formal recognition until the 20th century; the legal fiction was maintained that the Sovereign still governed directly. The position was first mentioned in statute only in 1917, in the schedule of the Chequers Estate Act. Increasingly during the 20th century, the office and role of Prime Minister featured in statute law and official documents; however, the