The Proclamation Declaring the Establishment of the Commonwealth was a royal proclamation made by Queen Victoria on 17 September 1900 federating the six separate British colonies of New South Wales, Queensland, South Australia, Tasmania, Victoria and Western Australia under the name of the Commonwealth of Australia. The proclamation, which took effect on 1 January 1901, was issued under the authority granted by the Commonwealth of Australia Constitution Act 1900, an Act of the Parliament of the United Kingdom.