Lansdowne, HENRY PETTY FITZMAURICE, third MARQUIS OF, was the son of the first marquis, better known as the Earl of Shelburne (q.v.), and was born in London, July 2, 1780. He received his education at Westminster School, Edinburgh University, and Trinity College, Cambridge, where he graduated in 1801. Born in the purple of politics, he was returned for the burgh of Calne at the age of twenty-two. He ranked himself among the opponents of Pitt, and took a leading part in that attack on Lord Melville which brought home to him the charge of corruption. When Pitt died Lord Henry Petty—as he was then styled—succeeded him as member for Cambridge University, and also as Chancellor of the Exchequer in the administration of 'All the Talents' formed by Lord Grenville, but held office for about a year only. In 1809, and after having represented the borough of Camelford for a short time, he succeeded by the death of his half-brother to the marquisate of Lansdowne. A sincere though cautious Liberal, he in 1826 entered the Canning cabinet; and in the short Goderich administration he presided at the Foreign Office. When, in 1830, the Whigs came into power under Lord Grey, Lansdowne became President of the Council, and took an active part in the passing of the Reform Bill of 1832. He held this office, with a short interval, till September 1841. Five years later, under Lord John Russell, he resumed his post, taking with it the leadership of the House of Lords, and held it till 1852. In that year he was requested to form an administration, but consented to serve without office in the coalition cabinet of Lord Aberdeen. When that ministry fell in 1855, Lansdowne was again asked to accept the premiership, but he once more declined, although he consented to help Lord Palmerston as he had helped Lord Aberdeen. He refused a dukedom. After the death of the Duke of Wellington Lansdowne was recognised as the patriarch of the House of Peers, while almost up to his death his advice was asked at his seat of Bowood by the leaders of the Liberal party. He was the attached personal friend of the Queen. Fond of literature and of the company of men of letters, he formed a great library, and one of the best collections of pictures and statuary in the kingdom. He died January 31, 1863.
The political biographies of the period in which Lansdowne lived abound in references to him. A considerable number of his letters on public affairs appear in Lord Melbourne's Papers, edited by Lloyd C. Sanders (1889). The Life of Lord John Russell, by Spencer Walpole (1889), illustrates in a remarkable manner the quiet but great influence exerted by Lansdowne in the councils of his party.