the leading Australian political figure during the first half of the 19th century, whose lifelong work for self-government culminated in the New South Wales constitution of 1855.

Wentworth became a public figure in 1813, when his crossing of the Blue Mountains near the coast of New South Wales opened up a vast new area for grazing. His book A Statistical, Historical, and Political Description of the Colony of New South Wales and Its Dependent Settlements in Van Diemen's Land (1819) publicized opportunities for colonization and argued for a liberal voting franchise. In 1824 he started a newspaper, the Australian, utilizing it and the Australian Patriotic Association, which he headed in 1835, to campaign for representative government.

After 1837 Wentworth sided with the large landowners and others who wanted a property-based franchise. He continued to work for home rule, making possible the Constitution Act of 1842, which provided for the election (rather than appointment) of two-thirds of the Legislative Council in New South Wales, and the constitution of the colony adopted in 1855. In 1853 he made the earliest proposal for federal government in Australia and led the upper house in 1861. He also helped to establish state primary education and the first Australian university, at Sydney, in 1850. He retired to England in 1862.