The decade was marked by the ascent of women to top positions in politics throughout the world. Isabel Peron of Argentina became the first woman to be president of a country. Margaret Thatcher became the prime minister of the United Kingdom in 1979. The Paris Peace Accords saw the end of the Vietnam War, which also resulted in victory for the Communist North. Iran also underwent a transition from a monarchy under ashah, to an Islamic republic established under the guidance of Ayatollah Ruhollah Khomeini. Filipinos, meanwhile, had to adjust to a life under martial law, which was eventually lifted in 1981.