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
Deputy Prime Minister of Sweden Deputy Prime Minister of Sweden The Swedish constitution allows the Prime Minister to appoint one of the Ministers in the cabinet as Deputy Prime Minister ("statsministers ställföreträdare", sometimes unofficially known as "vice statsminister"), in case the Prime Minister for some reason is prevented from performing his or her duties. If a Deputy Prime Minister has not been appointed, the Minister in the cabinet who has served the longest time (and if there are several with equal experience the one who is oldest) takes over as head of government (these are marked in "italic" in the table below). A Deputy Prime