Henry Dundas, 1st Viscount Melville, PC, FRSE (28 April 1742 – 28 May 1811), styled as Lord Melville from 1802, was a British politician who served as Home Secretary from 1791 to 1794 and First Lord of the Admiralty from 1804 to 1805. He was instrumental in the encouragement of the Scottish Enlightenment, in the prosecution of the war against France, and in the expansion of British influence in India.
Prime Minister William Pitt appointed him Lord of Trade (1784–1786), Home Secretary (1791–1794), President of the Board of Control for Indian Affairs (1793–1801), Secretary at War (1794–1801) and First Lord of the Admiralty (1804–1805). As a political boss, Dundas' deft and almost absolute power over Scottish politics during a long period in which no monarch visited the country led to him being nicknamed "King Harry the Ninth", the "Grand Manager of Scotland" (a play on the masonic office of Grand Master of Scotland), and "The Uncrowned King of Scotland." He was, however, a controversial figure, over his amendment to a motion for abolition of the Atlantic slave trade, which called for gradual abolition. At that time, the leaders of the abolitionist movement sought an immediate end to the slave trade, while the West Indian interests opposed any abolition at all.