What year was the Federation referendum held?

Referendums on federation were held in the Australian colonies between 1898 and 1900. The first round of referendums took place in 1898 in New South Wales, Victoria, South Australia, and Tasmania. New South Wales fell just short of the required Yes vote, prompting a second round of negotiations and referendums in 1899 and 1900 across all six Australian colonies.

The first referendums in 1898 produced mixed results. Victoria voted Yes by a comfortable margin (100,520 Yes to 22,099 No). South Australia voted Yes (35,800 Yes to 17,320 No). Tasmania voted Yes (11,797 Yes to 2,716 No). New South Wales narrowly fell short: 71,595 voted Yes and 66,228 No, but the colony's Enabling Act required at least 80,000 Yes votes to pass. Queensland and Western Australia did not hold first-round referendums.

After the NSW result, the colonial premiers met in Melbourne in early 1899 to negotiate amendments addressing NSW concerns. The amendments included the relocation of the future federal capital from Sydney's preferred location to a compromise site in southern NSW at least 100 miles from Sydney (section 125 of the Constitution), changes to the financial arrangements between the Commonwealth and the states, and various adjustments to the Senate's powers. The Henry Parkes compromise on the capital location resolved one of the most contentious issues.

The second-round referendums in 1899 and 1900 produced Yes majorities everywhere. NSW voted Yes on 20 June 1899 (107,420 Yes to 82,741 No). Victoria voted Yes on 27 July 1899 (152,653 to 9,805). South Australia voted Yes on 29 April 1899 (65,990 to 17,053). Tasmania voted Yes on 27 July 1899 (13,437 to 791). Queensland voted Yes on 2 September 1899 (38,488 to 30,996, the narrowest result). Western Australia held its referendum last, on 31 July 1900, after extensive debate and several local concerns about federal control of tariffs and railways. WA voted Yes by 44,800 to 19,691, completing the federation process. The Commonwealth of Australia Constitution Act 1900 was then passed by the British Parliament on 5 July 1900 (with WA still to vote at that point) and received royal assent from Queen Victoria on 9 July 1900.