In January 1840 he entered Lord Melbourne's administration as lord privy seal, and from the death of Lord Holland in the autumn of that year Lord Clarendon also held the office of chancellor of the duchy of Lancaster until the dissolution of the ministry in 1841. Deeply convinced that the maintenance of a cordial understanding with France was the most essential condition of peace and of a liberal policy in Europe, he reluctantly concurred in the measures proposed by Lord Palmerston for the expulsion of the pasha of Egypt from Syria; he strenuously advocated, with Lord Holland, a more conciliatory policy towards France; and he was only restrained from sending in his resignation by the dislike he felt to break up a cabinet he had so recently joined.
The interval of Sir Robert Peel's great administration (1841-1846) was to the leaders of the Whig party a period of repose; but Lord Clarendon took the warmest interest in the triumph of the principles of free trade and in the repeal of the corn-laws, of which his brother, Charles Pelham Villiers (q.v.), had been one of the earliest champions. For this reason, upon the formation of Lord John Russell's first administration, Lord Clarendon accepted the office of president of the Board of Trade. Twice in his career the governor-generalship of India was offered him, and once the governor-generalship of Canada;--these he refused from reluctance to withdraw from the politics of Europe. But in 1847 a sense of duty compelled him to take a far more laborious and uncongenial appointment. The desire of the cabinet was to abolish the lord-lieutenancy of Ireland, and Lord Clarendon was prevailed upon to accept that office, with a view to transform it ere long into an Irish secretaryship of state. But he had not been many months in Dublin before he acknowledged that the difficulties then existing in Ireland could only be met by the most vigilant and energetic authority, exercised on the spot. The crisis was one of extraordinary peril. Agrarian crimes of horrible atrocity had increased threefold. The Catholic clergy were openly disaffected. This was the second year of the Irish famine, and extraordinary measures were required to regulate the bounty of the government and the nation. In 1848 the revolution in France let loose fresh elements of discord, which culminated in an abortive insurrection, and for a lengthened period Ireland was a prey to more than her wonted symptoms of disaffection and disorder. Lord Clarendon remained viceroy of Ireland till 1852, and left behind him permanent marks of improvement. His services were expressly acknowledged in the queen's speech to both Houses of Parliament on the 5th of September 1848--this being the first time that any _civil_ services obtained that honour; and he was made a knight of the Garter (retaining also the grand cross of the Bath by special order) on the 23rd of March 1849.