Major Sir Thomas Livingstone Mitchell lived from 16 June 1792 to October 1855. He became the Surveyor-General of New South Wales. The wider picture in Scotland at the time is set out in our Historical Timeline.
Thomas Mitchell was born at Grangemouth, a port on the south bank of the River Forth. He studied at the University of Edinburgh before joining the army in 1811. He served in Portugal, where he met Sir George Murray, who would later become Colonial Secretary in the Government in London. Mitchell trained to be a surveyor in the army, and in 1817 married Mary Blunt in Lisbon.
In 1827, Mitchell's link with Sir George Murray helped him secure the position of Surveyor-General of New South Wales. At the time, little was known about the detailed geography of the colony. Yet new settlers were arriving all the time and the Colonial Government needed good maps, if only to establish a basis for land sales. Among Mitchell's early contributions were surveying the route of the Great North Road linking Sydney to the Hunter Valley and the Great South Road linking Sydney and Goulburn. In 1834 he surveyed and produced a map of the "nineteen counties", the area marking the extent of settlement at the time. His map proved so valuable he was awarded a knighthood.
Meanwhile, Mitchell was keen to discover and map the geography of the interior of New South Wales, the vast areas beyond what had so far been settled. He undertook four expeditions to try to fill in the blanks on the map. The first, in late 1831, explored the area including the Gwydir River. The second, in 1835, followed the course of the Darling River, while the third and fourth, in 1836, explored the area of the Murray River. Mitchell's accounts of his expeditions continue to provide valuable information for historians and anthropologists, and are especially strong in their descriptions of the Aboriginal peoples he had encountered. As a result of his journals he became the most famous Australian explorer of his time.
Mitchell died in Sydney in 1855. He is remembered in many ways in Australia. The Major Mitchell's Cockatoo is named after him, as are the town of Mitchell in Queensland, the Mitchell's Hopping Mouse, Mitchell Falls, the Mitchell Highway, Mitchell College, Mitchell Park, Mitchell Plateau, Sir Thomas Mitchell Road in Bondi Beach, Mitchell's Lookout and Mitchell River.