STEWART (afterwards Vane), CHARLES WILLIAM, third Marquis of Londonderry (1778–1854), was the only son of Robert Stewart, first marquis [q. v.], by his second wife, Frances, eldest daughter of Charles Pratt, first earl Camden [q. v.] He was born in Dublin on 18 May 1778, being nine years younger than his half-brother Robert, second marquis, better known as Lord Castlereagh [q. v.] He was educated at Eton, and narrowly escaped drowning there at the age of thirteen in a courageous attempt to save his schoolfellow, Lord Waldegrave. He was commissioned as ensign in a newly raised regiment of foot (Macnamara's) on 11 Oct. 1794, in which he became lieutenant on 30 Oct. and captain on 12 Nov. He obtained a majority in the 106th foot on 31 July 1795, but both this and his former regiment were disbanded in that year. He was employed on the staff of Lord Moira's corps in the campaign of 1794–5 in the Netherlands. He then accompanied Colonel (afterwards Sir Charles Gregan-) Craufurd [q. v.] to the headquarters of the Austrian army, and served with it in the campaigns of 1795–6 on the Rhine and Upper Danube. In a cavalry affair near Donauwörth he was struck by a bullet under the left eye and his sight injured.
He was aide-de-camp to his uncle, Lord Camden, who was lord-lieutenant of Ireland from 1795 to 1798. On 4 Aug. 1796 he obtained a majority in the 5th dragoons (Royal Irish), and became lieutenant-colonel of it on 1 Jan. 1797. The regiment served in Ireland during the rebellion of 1798; but its discipline became so bad, and so many disloyal men were found to be in its ranks, that it was disbanded on 8 April 1799. Stewart had done his utmost to improve it; his family interest was great, and four days afterwards he was made lieutenant-colonel of the 18th light dragoons.
He served with two squadrons of this regiment in the short campaign of 1799 in Holland. Being attached to Abercrombie's division on 19 Sept., and to Pulteney's on 2 Oct., he had little fighting. He was slightly wounded on outpost duty at Schagenburg on 10 Oct. On 25 Sept. 1803 he was made aide-de-camp to the king and colonel in the army. Shortly afterwards he was appointed under-secretary in Ireland. He had been elected member for Thomastown to the Irish parliament in 1798, and after the union he was member for co. Derry in the imperial parliament till 1814. In 1805, when invasion was threatened, he published ‘Suggestions for the Improvement of the Force of the British Empire.’ In 1807 he became under-secretary for war, Castlereagh being the secretary of state. The two brothers were always most warmly attached to each other.
In August 1808 Stewart left his office for a time to command the hussar brigade in the corps sent out to Portugal under Sir John Moore. The brigade consisted of the 18th and the king's German hussars, to which the 10th was afterwards added. It covered the advance of Hope's division upon Madrid and Salamanca in November, and afterwards covered the retreat of the whole army on Coruña. On 12 Dec. Stewart surprised a French post at Rueda and took eighty prisoners; and on the 28th he had a prominent part in the brilliant cavalry action at Benavente, the pickets being furnished by his regiment. He shared with Lord Paget the praise of Moore, that they had put the right spirit into the British cavalry.
He returned to England and to his office in January 1809. He was given the governorship of Fort Charles, Jamaica—a sinecure office worth 650l. a year, which he resigned in favour of Lord Bloomfield in 1822. In April 1809 he went back to Portugal as adjutant-general under Wellesley, with the rank of brigadier-general. At the passage of the Douro he led some charges of squadrons which were specially noticed by Wellesley in general orders, and he also distinguished himself at Talavera. Ill-health obliged him to go to England for the winter, and on 5 Feb. 1810 he received, in his place in parliament, the thanks of the House of Commons. He was promoted major-general on 25 July.
He returned to the Peninsula in March, and served as adjutant-general throughout the campaigns of 1810 and 1811. He was mentioned in despatches for Busaco and Fuentes d'Onoro. In the latter battle he disarmed a colonel of chasseurs and made him prisoner, and at El Bodon he found fresh opportunity of taking part in a cavalry encounter. He was essentially a sabreur, handsome and dashing; in Alison's words, ‘his nature was chivalrous rather than administrative;’ and he longed to exchange his staff appointment for a cavalry command. But Wellington would not indulge him. On 25 June 1811, in reply to a letter from the Duke of York, he wrote that Stewart was a very gallant and very able officer of cavalry, but, owing to his defective sight and hearing, his gallantry would be apt to lead him into difficulties.
Stewart was at the siege and capture of Ciudad Rodrigo in January 1812, but a return
