Prime Minister of Australia prime minister, otherwise William McMahon63. Robert Menzies was the oldest person to ever be prime minister, leaving office at 71 years old. The longest-serving Prime Minister was Sir Robert Menzies, who served in office twice: from 26 April 1939 to 28 August 1941, and again from 19 December 1949 to 26 January 1966. In total Robert Menzies spent 18 years, 5 months and 12 days in office. He served under the United Australia Party and the Liberal Party respectively. The shortest-serving Prime Minister was Frank Forde, who was appointed to the position on 6 July 1945 after the death of
Spouse of the Prime Minister of Australia most notably Dame Enid Lyons (1932–39), who had 12 children (one died in infancy). In 1943, four years after her husband's death in office, she was the first woman to be elected to the House of Representatives. She was a junior minister in the Menzies Government from 1949 to 1951. Some Prime Ministers' spouses have received official recognition for their services to the community: Tamie Fraser was the first spouse of a Prime Minister to be provided with an official secretary for dealing with her correspondence. There are currently seven living spouses of former prime ministers of Australia: The most