Thomas Smythe, son of Sir John, was made a knight of the Bath in 1616, ‘being a person of distinguished merit and opulent fortune;’ and on 17 July 1628 was created an Irish peer by the title of Viscount Strangford of Strangford, co. Down. He died on 30 June 1635, having married Lady Barbara, seventh daughter of Robert Sidney, first earl of Leicester [q. v.]
Percy, the sixth viscount, graduated in 1800 at Trinity College, Dublin, where he won the gold medal. In 1802 he entered the diplomatic service as secretary of the legation at Lisbon. In the following year he published ‘Poems from the Portuguese of Camoëns, with Remarks and Notes’ (cf. Edinb. Rev. April 1805). Byron, in ‘British Bards and Scotch Reviewers,’ accused the translator of teaching ‘the Lusian bard to copy Moore,’ and described him as
Hibernian Strangford, with thine eyes of blue,
And boasted locks of red or auburn hue.
The ‘Poems’ were frequently reissued, the last edition in 1828, in which year a French version also appeared (Moore, Life of Byron, p. 39).
Strangford soon became a persona grata at the Portuguese court. In 1806 he was named minister-plenipotentiary ad interim. He persuaded the prince regent of Portugal, on the advance of the French in November 1807, to leave Portugal for Brazil. Strangford arrived in England on 19 Dec., and drew up, by Canning's desire, a connected account of the proceeding drawn from his own despatches. It was published in the ‘London Gazette’ on 22 Dec. In 1828 Napier, in the first volume of his ‘Peninsular War,’ maintained that the credit of the diplomatic negotiations really belonged to Sir William Sidney Smith [q. v.], and made various charges against Strangford. The latter issued ‘Observations’ in reply, which Sir Walter Scott and even the whig circles at Holland House thought satisfactory (Scott, Journal, 31 May 1828; Moore, Diary, 21 May). Napier rejoined, and Strangford issued ‘Further Observations.’ Strangford failed to obtain legal redress for some strong reflections made on him in the same connection by the ‘Sun’ newspaper. Brougham appeared for the defendants at the trial (Napier, Peninsular War, 1851, vi. 222–3).
Strangford received the order of the Bath, and was sworn of the privy council in March 1808. On 16 April he was appointed envoy-extraordinary to the Portuguese court in Brazil. He was made G.C.B. on 2 Jan. 1815, on his return from the mission.
On 18 July 1817 he became ambassador to Sweden. Before leaving Stockholm, two years later, he induced the Swedish government to agree to the English proposals for an arrangement with Denmark, and discussed with them a new tariff highly advantageous to England. On 7 Aug. 1820 Strangford was appointed ambassador at Constantinople. Here he joined the Austrian minister in urging on the Porte the necessity of pursuing more conciliatory conduct towards Russia, and of making concessions to its Christian subjects, then in open revolt both in Greece and the Danubian provinces. In the autumn of 1822 he went to Verona, and laid before the European congress the assurances he had obtained from the sultan. When, in December, Strangford returned to Constantinople, he was charged with the sole care of Russian affairs in Turkey. He obtained from the Porte the evacuation of the Danubian principalities, the conclusion of a treaty allowing Sardinian ships to enter the Bosphorus, and the removal of the recently made restrictions on Russian trade in the Black Sea. In return the tsar promised the resumption of diplomatic relations with Turkey. On 13 Sept. 1824 Wellington wrote to Strangford congratulating him ‘upon a result obtained by your rare abilities, firmness, and perseverance’ (Wellington Corresp. ii. 308, 309). Greville charged him with having exceeded his instructions while at Constantinople; but these, Strangford complained afterwards, were scanty (Journal of Reign of George IV, p. 140; cf. Wellington Corresp. iv. 167). In October he left Turkey. A year later Strangford went as ambassador to St. Petersburg at the special request of the tsar. He had been found rather too watchful an observer of Russian designs at Constantinople, and was transferred to St. Petersburg. He remained at St. Petersburg only a few months, during which he pressed the tsar to fulfil his promise of resuming relations with the Porte. After his return from Russia, in 1825, Strangford was created a peer of the United Kingdom with the title of Baron Penshurst of Penshurst in Kent. In a speech in the House of Lords on 7 June 1827 he stated that he had served under nine foreign secretaries (Parl. Debates, new ser. xvii. 1139). His diplomatic career closed with a special mission to Brazil in August 1828. For the remainder of his life he was an active tory peer, often taking part in debates on questions of foreign policy. On 29 Jan. 1828 he seconded the address (ib. xviii. 8–11). On 11 Aug. 1831 he complained that the arrangements for the coronation of William IV had not been submitted to the privy council, but
