Founded by free settlers from the British Crown colony of Van Diemen's Land on 30 August 1835, in what was then the colony of New South Wales, it was incorporated as a Crown settlement in 1837. It was named "Melbourne" by the Governor of New South Wales, Sir Richard Bourke, in honour of the British Prime Minister of the day, William Lamb, 2nd Viscount Melbourne. It was officially declared a city by Queen Victoria in 1847, after which it became the capital of the newly founded colony of Victoria in 1851. During the Victorian gold rush of the 1850s, it was transformed into one of the world's largest and wealthiest cities. After the federation of Australia in 1901, it served as the nation's interim seat of government until 1927.