When was Australia founded?

Australia was founded on 26 January 1788, but it became 'The Commonwealth of Australia' upon federation of the states on 1 January 1901.

In 1788 the British Government established a penal colony on the east coast of the continent called Terra Australis, which had been claimed by James Cook under the name of New South Wales when he charted it in 1770. (Originally, the Dutch called the western half of the continent New Holland.) The term 'Australia' was adopted for the continent in 1824, but it did not become a country until Federation in 1901.