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
Australian home front during World War II democratic government in the Southern World". In April 1944, Curtin held talks on postwar planning with President Franklin Roosevelt of the US and with Prime Minister Winston Churchill of Britain and gained agreement for the Australian economy to begin transitioning from military to post-war economy. He returned to Australia and campaigned for an unsuccessful 1944 referendum to extend federal government power over employment, monopolies, Aboriginal people, health and railway gauges. Prime Minister Curtin suffered from ill health from the strains of office. He suffered a major heart attack in November 1944. Facing the newly formed Liberal Party of Australia opposition