John Warby (1774?-1851), convict and explorer, was convicted at Hertford, England, on 3 March 1791 and sentenced to transportation for seven years. He reached Sydney in February 1792 in the Pitt. At Parramatta on 12 September 1796 he married Sarah Bentley (1780-1869), a convict who had arrived in the Indispensable in April 1796; they had nine sons and five daughters.

After his sentence expired Warby acquired fifty acres (20 ha) at Prospect and in 1803 was appointed stockman of the wild cattle at large in the Cowpastures. It was along Warby's track leading from his home through the Cowpastures that James Meehan made a line of road in 1805. In 1806 Warby was a constable of Camden County, and he was one of those who signed a respectful address to Governor William Bligh on 1 January 1808. He guided Governor Lachlan Macquarie and his party from Prospect Hill through the Cowpastures in November 1810 and again in October 1815 on an expedition into the rough country along the Nattai River. He was one of the first to explore the Oaks, the Bargo area and the Burragorang Valley, and continued to be in demand as a guide. Thus in 1814 he was among those rewarded for visiting Aboriginal tribes in the inland area and for arresting Patrick Collins, a bushranger, and in 1816 for guiding soldiers who were pursuing Aboriginal tribes.

In June 1816 he was granted 260 acres (105 ha) at Campbelltown and there built a house where he died on 12 June 1851. His widow died at Campbelltown on 19 October 1869.