Former British Prime Minister Margaret has died at age 87 following a stroke. Her spokesman, Lord Bell, said that her family announced with great sadness that “she had died peacefully following a stroke this morning." Thatcher had been in ill health for many months. Thatcher, nicknamed the “Iron Lady,” is credited with helping to pull down the Iron Curtain. As Britain's only woman prime minister, she won three elections and governed from 1979 to 1990 -- the longest continuous period in office by a British prime minister since the early 19th century.