The first seamen’s unions in Australia were formed in Melbourne (1872) and in Sydney (1874). In 1876 the Melbourne Seamen’s Union and the Sydney Seamen’s Union amalgamated and, by 1880, there were seamen’s unions in all the eastern and south-eastern colonies of Australia as well as in several ports in New Zealand. The Federated Seamen's Union of Australasia was registered in 1906 under the Commonwealth's industrial relations legislation and, in 1907, Head Office was transferred from Melbourne to Sydney. Although the Federated Seamen's Union of Australasia was deregistered in 1925, in 1930 many of its members went on to form the Seamen's Union of Australasia which, in 1943, became the Seamen’s Union of Australia. Despite amalgamations with the Marine Cooks, Bakers and Butchers' Association of Australia in 1983, the Federated Marine Stewards and Pantrymen’s Association of Australasia in 1988 and the Professional Divers' Association in 1991, it remained the Seamen's Union of Australia until 1993 when it amalgamated with the Waterside Workers' Federation to form the Maritime Union of Australia.