Employees at Conservative Party HQ remember Thatcher Former prime minister Margaret Thatcher, the controversial "Iron Lady" who dominated a generation of British politics and won international acclaim for helping to end the Cold War, has died following a stroke. She was 87. She was first elected to the House of Commons in 1959 as an MP for Finchley and succeeded former prime minister Edward Heath as opposition Conservative leader in 1975 before becoming premier four years later. Images and soundbites of the Conservative Party Headquarters in Finchley, North London