Margaret Thatcher was known as the "Iron Lady" of British politics. She earned this nickname due to her strong and uncompromising leadership style during her time as Prime Minister from 1979 to 1990. A member of the Conservative Party, Thatcher implemented significant economic reforms, including reducing the power of trade unions and promoting free-market policies. Her leadership style and policies often polarized public opinion, leading to both strong support and fierce opposition. She became an iconic figure in British history and remains a symbol of conservative politics, earning recognition for her leadership during the Cold War.