On his retirement from office Malmesbury was created G.C.B.
In May 1860 Malmesbury made an offer to Lord Palmerston in the names of Lord Derby and Disraeli of support against his own colleagues, Lord John Russell and Mr. Gladstone, if they resigned on the postponement of the Reform Bill, and in 1861, during a visit to Paris, attempted to remove the emperor's prejudices against the conservative party. In 1863 he made a creditable effort to induce the French government to surrender the statues of Henry II, Richard I, and their queens, which are in the vaults of the abbey of Fontevrault, but without success, though the attempt was renewed in 1866. In the absence of Lord Derby, Malmesbury moved, on 8 July 1864, the vote of censure on Lord Palmerston's government for its management of the Danish question, and carried it by a majority of nine; but the opposition was defeated by eighteen in the lower house, and the liberals remained in power until 1866. On the formation of Lord Derby's third ministry, in June of that year, Malmesbury declined the foreign office in consequence of ill-health, and accepted the post of lord privy seal. During the Reform Bill agitation he made a speech at Christchurch in denial of Mr. Bright's statement that the House of Lords was hostile to reform, and in the following session attempted to dissuade Lord Derby from introducing the ‘Six Minutes’ Bill. He conducted the Reform Bill through the House of Lords, where an amendment was carried against him by Lord Cairns raising the lodger franchise from 10l. to 15l. In February 1868, on the resignation of Lord Derby, he became leader of the House of Lords, and proved successful, in spite of his somewhat slipshod oratory; but in December he retired in favour of Lord Cairns. On 27 April and 8 July 1869 he made important speeches on the Life Peerages Bill, and succeeded in getting it rejected by 106 votes to 77. He was again lord privy seal in 1874, under Disraeli, but resigned in 1876 owing to increasing deafness. One of his last appearances was in 1881, when he supported the proposal to place a statue of Lord Beaconsfield in Westminster Abbey.
Besides his grandfather's journal mentioned above, Malmesbury published in 1870 a selection entitled ‘A Series of Letters of the First Earl of Malmesbury, his Family, and Friends, from 1745 to 1820.’ In 1884 his own ‘Memoirs of an Ex-Minister’ appeared in two volumes, and promptly went into a fourth edition. They comprise a preface dealing with events between 1807 and 1834, and ‘a macédoine of memoranda, diary, and correspondence,’ concluding with an account of an interview with Napolean III at Chislehurst on 21 March 1871. His principal object was to sketch ‘the three administrations of the late Earl of Derby, whose colleague I was, and also some incidents respecting one of the most remarkable men of this century, namely, the Emperor Louis Napoleon.’ The book also gives us a good idea of Disraeli's earlier career as a conservative leader, and incidentally depicts Malmesbury himself as a man of considerable abilities and statecraft, of much urbanity and amiability in private life, and a devoted sportsman. The non-political portion of the book contains accounts of visits to the continent, court and society gossip, and well-told, if sometimes racy, anecdotes (see letters to the ‘Times’ by Lord Granville of 7 Oct., Sir A. Borthwick 14 Oct., Earl Grey 22 Oct., Lord Malmesbury, embodying a correction from Mr. Gladstone, 3 Dec.)
Malmesbury married, first, on 13 April 1830, Lady Emma Bennet, only daughter of the fifth Earl of Tankerville; she died 17 May 1876. Her portrait, painted by Edwin Landseer in 1833, which was received by Malmesbury from Landseer's executors in 1877, now hangs at Heron's Court, Hampshire; secondly, in 1880, Susan, the daughter of John Hamilton of Fyne Court House, Somersetshire, but leaving no issue was succeeded on his death, on 17 May 1889, by his nephew, Colonel Edward James Harris, son of his second brother, Edward (see below).
Harris, Sir Edward Alfred John (1808–1888), admiral, second brother of the above, was born 20 May 1808, and educated with his brother till 1822, when he went to the Royal Naval College, Portsmouth, and next year entered the royal navy as midshipman on board the Isis; he became lieutenant in February 1828, and rose through the various ranks till he was appointed admiral on the reserved list in 1877. From 1844 to 1852 he represented Christchurch in parliament; in 1852 he was appointed consul-general in Denmark, but was in the same year transferred to Lima as chargé d'affaires and consul-general; the latter post he exchanged for a similar one in Chili in January 1853. In 1858 he was appointed consul-general for the Austrian coasts of the Adriatic, and afterwards minister at Berne; in 1867 he was transferred to the Hague. He was made a K.C.B. in 1872, and retired on a pension in November 1877. He died 17 July 1888; having married (4 Aug. 1841) Emma Wyly, daughter of Captain Samuel Chambers, R.N., he left, with other issue, Edward James, now fourth