Barton was an early supporter of the federation of the Australian colonies, the goal of which he summarised as "a nation for a continent, and a continent for a nation". After the retirement of Henry Parkes he came to be seen as the leader of the federation movement in New South Wales. He was a delegate to the constitutional conventions, playing a key role in the drafting of a national constitution, and was one of the lead campaigners for federation in the subsequent referendums. In late 1900, despite the initial "Hopetoun Blunder", Barton was commissioned to form a caretaker government as Australia's first prime minister. His term began on 1 January 1901, the date on which federation occurred.