1901    The British colonies of New South Wales, Queensland, Victoria, South Australia, Tasmania and Western Australia federate as the Commonwealth of Australia; Edmund Barton is appointed the first Prime Minister.

1905    Alfred Deakin becomes Prime Minister of Australia for the second time.

1909    Alfred Deakin becomes Prime Minister of Australia for the third time.

1914    Andrew Fisher becomes Prime Minister of Australia for the third time.

1916    Prime Minister of Australia Billy Hughes is expelled from the Labor Party over his support for conscription.

1964    Prime Minister of Australia Robert Menzies opens the artificial Lake Burley Griffin in the middle of the capital Canberra.

1967    Prime Minister of Australia Harold Holt disappears while swimming near Portsea, Victoria and was presumed drowned.

1967    Prime Minister of Australia Harold Holt is officially presumed dead.

1975    Australian constitutional crisis of 1975: Australian Governor-General Sir John Kerr dismisses the government of Gough Whitlam, appoints Malcolm Fraser as caretaker Prime Minister and announces a general election to be held in early December.

2007    Australians elect the centre-left Australian Labor Party at a federal election; the outgoing prime minister, John Howard, becomes the first since 1929 to lose his own seat.