STEWART, ROBERT, second Marquis of Lon donderry, best known as VISCOUNT CASTLEREAGH (1769-1822). An eminent English statesman. He was the eldest surviving son of Robert, first Marquis of Londonderry, and was educated at Saint John's College. Cambridge. He entered the Irish Parliament in 1790 at the age of twenty one. In 1796 he became Viscount Castlereagh; and in 1798 he was made Chief Secretary for Ireland. In suppressing the rebellion of that year he was resolute and energetic. In helping to bring about the Parliamentary union with Eng land lie made free use of English money in corrupting opponents of the plan. He entered the Imperial Parliament, and in 1805-06 was Secretary of State for the War and Colonial departments. Resigning on Pitt's death in 1806. he resumed the office of War Minister next year. and organized the disas trous Walcheren expedition ( 1809 ) . Canning (q.v.). then Foreign Secretary, attacked Castle reagh on this account with much bitterness. The result was that both resigned, and a duel took place between them. September 21. 1809. in which Canning was wounded. After the assassination of Perceval in 1812, Castlereagh became Foreign Secretary. a post which he held during the period famous for the achievements of the Duke of Wellington. By this time the general direc
tion of British policy was unalterably fixed by circumstances, and it was the merit of Castle reagh that lie pursued this course with steadi ness even obstinacy. His personal influence and his untiring exertions kept together the coalition against Napoleon. He represented Eng land at the Congress of Vienna in 1814-15, at the Treaty of Paris in 1815, and at the Congress of Aix-la-Chapelle in 1818. His foreign policy was favorable to the principles of the `Holy Alliance' abroad and he constantly recom mended despotic measures at home. As the leader of the Liverpool Government in the Lower House, he carried the suspension of the Habeas Corpus Act in 1817. The 'Six Acts' of 1S19 made him extremely unpopular. The retirement of Canning from the Ministry (1820) threw the whole weight of business on Castlereagh. By the death of his father in 1S21 he became Marquis of Londonderry. The great toil and responsi bility of his ollice deranged his mind, and he died by his own hand at his seat at North Cray Place, Kent, August 12, 1822. Consult his Memoirs and Correspondence (12 vols., London, 1848-53).