William Lamb Melbourne, 2d Viscount (mĕl´bərn), 1779–1848, British statesman. He entered Parliament as a Whig in 1805, was (1827–28) chief secretary for Ireland, and entered (1828) the House of Lords on the death of his father. As home secretary (1830–34) for the 2d Earl Grey, his vigorous suppression of agrarian disturbances and trade unionism (see Tolpuddle Martyrs) ended a reputation for indolence. A believer in aristocratic government, unsympathetic with middle-class political and economic aims, Melbourne accepted the Reform Bill of 1832 as a political necessity.
As prime minister (1834, 1835–39, 1839–41) his views brought him support from Whigs and moderate Tories, and he excluded radicals from his ministries. He conceded such reforms as amendment of the poor law (1834), the Municipal Corporations Act (1835), and liberalization of the Canadian government. He was also conciliatory in his policy toward Ireland. However, he resisted further parliamentary reform and repeal of the corn laws.
Melbourne viewed the prime ministership as a supervisory position; cabinet members, such as Lord Palmerston, played a vital role in developing policy. Handsome and urbane, Melbourne was a favorite of the young Queen Victoria and taught her important lessons in statecraft. It was at her request that he returned to office (1839) after Sir Robert Peel resigned over a disagreement with the queen.
Melbourne's wife, Lady Caroline Lamb, 1785–1828, was clever and beautiful, but also eccentric, impulsive, and indiscreet. She is remembered less for the minor novels that she wrote than for her love affair with Lord Byron. Lady Caroline and her husband separated in 1825.
See Lord Melbourne's papers (ed. by L. C. Sanders, 1889, repr. 1971); biography of him by Lord David Cecil (1954, repr. 1965); biography of his wife by H. Blyth (1972).