1804 in Australia

Incumbents

• Monarch - George III

  Governors

• Governor of New South Wales – Captain Philip King
• Lieutenant-Governor of Southern Van Diemen's Land – David Collins
• Lieutenant-Governor of Northern Van Diemen's Land – William Paterson

  Events

• 4 March – The Castle Hill convict rebellion, also known as the Battle of Vinegar Hill, takes place: 200 convicts, mostly Irish, rebel. Fifty-one convicts are punished, and nine hanged.
• 3 May – An Aboriginal food hunting party is attacked by settlers and soldiers at Risdon Cove. Eyewitness estimates of the death toll from the massacre vary from three or four to fifty.
• 16 September – A government-owned brewery is opened at Parramatta as a means of controlling the consumption of spirits.
• 4 November – In a letter to Sir Joseph Banks, Matthew Flinders recommends that the newly discovered country, New Holland, be renamed "Australia" or "Terra Australis".

  Exploration and settlement

• 15 February – Lieutenant-Governor David Collins lands at Risdon Cove in Van Diemen's Land. Unhappy with the area as a site for a settlement, Collins sends his surveyor, George Prideaux Harris, and harbour master William Collins in search of an alternative site. Harris and Collins recommend Sullivan's Cove.
• 24 March – The settlement at the Hunter River, also known as the Coal River, is officially named Newcastle.
• 8 May – Lieutenant-Governor Collins establishes the settlement at Sullivan's Cove on the Derwent River.
• 15 June – The name "Hobart Town", after the Colonial Secretary Lord Hobart, is adopted as the name for the new colony at Sullivan's Cove.
• 5 November – Lieutenant-Colonel William Paterson arrives at Outer Cove, leading the Buffalo, the Lady Nelson and two schooners, under instructions from London to form a settlement in the north of Van Diemen's Land.

  Births

• 5 October – Robert Campbell, politician

  Deaths

• 21 March – James Bloodsworth, convict and bricklayer
• 27 December – George Barrington, convict and police officer