Stewart, Robert, first Marquis of Londonderry 1739-1821, eldest son of Alexander Stewart of Ballylawn Castle, co. Donegal, and Mount Stewart, co. Down, M.P. for Londonderry, who died in 1781, by his wife Mary, sister and heir of Sir Robert Cowan, governor of Bombay, was born on 27 Sept. 1739. His family was very influential in the county Down; in 1769 he was elected one of the county members for the Irish parliament, and was re-elected in 1776, but lost the seat in 1783, and was a peer before the next election. He was undoubtedly a sagacious though never a prominent public man. During the Irish volunteer movement he was one of the delegates sent to the second Dungannon convention in 1783, and was one of its leading spirits. He was advanced to the peerage as Baron Londonderry on 20 Sept. 1789, having been previously sworn of the Irish privy council during Lord Lansdowne's administration, and appointed a trustee of the linen board. He was created Viscount Castlereagh on 6 Oct. 1795, Earl of Londonderry on 8 Aug. 1796, and was made Marquis of Londonderry on 22 Jan. 1816. He was also appointed in 1801 and 1803 governor and custos rotulorum of the county of Down and of Londonderry. His claims to be made a peer of the United Kingdom in 1800, in consideration of his son's services, though not pressed by himself or his son, were not unfavourably considered by the crown, and an assurance was given that if at any future time he or his descendants should desire a British peerage, their wish should be granted (Cornwallis Correspondence, ii. 273, iii. 274). Neither the father, however, nor the son claimed the fulfilment of this promise, probably to prevent Lord Castlereagh's removal from the House of Commons. He died at Castle Stewart on 8 April 1821. He was twice married: first, on 3 June 1766, to Lady Sarah Frances, second daughter of Francis Seymour Conway, marquis of Hertford [q.v.], by whom he had two sons, of whom Robert (1769-1822) [q.v.], the younger and surviving son, succeeded him; and secondly, on 7 June 1775, to Lady Frances, eldest daughter of Lord-chancellor Camden [see Pratt, Charles, first Earl Camden], by whom he had three sons and eight daughters. Of his second family, General Charles William Stewart (afterwards Lord Stewart and third Marquis of Londonderry) [q.v.], British ambassador at Vienna, was the eldest. In private life Londonderry was not only a very charitable man, but also enlightened. He resided on his estates almost exclusively, and encouraged tenant-right; he remitted rents; he made work for the unemployed, and brought supplies into the district for the distressed. To his family, and especially to the training and fortunes of his son, Lord Castlereagh, he was deeply devoted.
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