British careerist politician who held various ministerial offices under William Pitt the Younger and whose adroit control of Scottish politics earned him the nickname “King Harry the Ninth.” Educated at the University of Edinburgh, he became a member of the faculty of advocates in 1763 and soon acquired a leading position at the bar; but after his appointment as lord advocate in 1775, he gradually relinquished his legal practice to devote his attention more exclusively to public business. In 1774 he was returned to Parliament for Midlothian and joined the party of Lord North; and, notwithstanding his provincial dialect and ungraceful manner, he soon distinguished himself by his clear and argumentative speeches.

After holding subordinate offices under the Marquess of Lansdowne and Pitt, he entered the Cabinet in 1791 as home secretary. From 1794 to 1801 he was secretary at war under Pitt, who conceived for him a special friendship. In 1802 he was elevated to the peerage as Viscount Melville and Baron Dunira. Under Pitt in 1804 he again entered office as first lord of the Admiralty, when he introduced numerous improvements in the details of the department. Suspicion had arisen, however, as to the financial management of the Admiralty, of which Dundas had been treasurer between 1782 and 1800; in 1802 a commission of inquiry was appointed, which reported in 1805. The result was the impeachment of Lord Melville in 1806 for the misappropriation of public money; and though it ended in an acquittal, and nothing more than formal negligence lay against him, he never again held office. An earldom was offered in 1809 but declined.