George William Frederick Villiers, 4th Earl of Clarendon and 4th Baron Hyde (1800-1870), was the grandson of Thomas Villiers, 1st Earl of Clarendon of the second creation, and eldest son of the Hon. George Villiers (1759-1827) and his wife Theresa, only daughter of the first Lord Boringdon and granddaughter of Lord Grantham. He entered the diplomatic service at a young age as attaché to the British Embassy at St. Petersburg. In 1823 he was appointed commissioner of customs, and from 1827 to 1829 he was in Ireland arranging details of the English and Irish excise boards. His diplomatic career continued in France and Madrid, where he was held largely responsible for a successful conclusion of the 'quadruple alliance' treaty between England, Spain, France and Portugal. He further negotiated a treaty with the Spanish government with regard to the slave trade. In recognition of this and other diplomatic efforts he received the formal approbation of Lord Palmerston and was made a GCB by Lord Melbourne in 1837.
In the following year upon the death of his uncle John Charles, 3rd Earl of Clarendon, he succeeded to the Earldom. His career was at such a high point that the Spanish government struck a gold medal in his honour and it was rumoured that he would become premier. However, politics at home forced him to speak against the powerful Palmerston in regards to his Syrian policy. Well-versed in Irish politics and known to be liberal as regards Irish policy, he was appointed lord-lieutenant of Ireland from 1847 to 1852, and there became the focus of a great deal of hostility due to the famine and political disturbances at this time. Upon his return to England he succeeded to the secretaryship for foreign affairs just at the outset of the Crimean War. His personal influence with Napoleon was said to be invaluable in maintaining cooperation between the allies; and he negotiated the Peace of Paris on behalf of Great Britain. In 1868 he was made foreign secretary, but died two years later on 27 June 1870, at his house in Grosvenor Crescent, London.
He had married on 4 June 1839, Katherine, eldest daughter of Walter James Grimston, first earl of Verulam; they had three sons and three daughters. His son Edward Hyde succeeded him; and his other two sons entered the diplomatic service. The 4th Earl was considered in contemporary accounts to be a deeply learned man in all European affairs; a scholar of languages; an acute judge of character; a liberal; and an attractive and witter talker. He twice refused both the governor-generalship of India and a marquisate, and was further offered, but also refused, the order of the Prussian Black Eagle by the king of Prussia and the Legion of Honour by Napoleon III.