May he was made a K.C.B. In the same year Napier wrote some ‘Notes on the State of Europe.’ Towards the end of 1848 the Liverpool Financial Reform Association published some tracts attacking the system by which the soldiers of the army were clothed through the medium of the colonels of regiments. The association sent its tracts to Napier, himself a clothing colonel, upon which he wrote a series of six vindicatory letters to the ‘Times’ newspaper, dating 29 Dec. 1848 to 1 Feb. 1849. They form Appendix VII. to Bruce's ‘Life of General Sir William Napier.’
Napier moved in 1849 with his family to Scinde House, Clapham Park, where he spent the rest of his life. In 1850 his brother Charles, then commander-in-chief in India, resigned his command because he had been censured by Lord Dalhousie. He arrived in England in March 1851. Napier was indignant, and, after Sir Charles Napier's death, defended him in a pamphlet.
In 1851 Napier completed and published the ‘History of the Administration of Scinde.’ This work, recording the gradual introduction of good government into the country, contains some masterly narratives of the hill campaigns. In 1856 Carlyle read it, and wrote to Napier: ‘There is a great talent in this book, apart from its subject. The narrative moves on with strong, weighty step, like a marching phalanx, with the gleam of clear steel in them.’
When the Birkenhead transport went down in Simon's Bay, Cape of Good Hope, Napier, impressed with the heroism of the officers, and seeing no step taken to reward the survivors, wrote letters to every member of parliament he knew in both houses. The result was that Henry Drummond brought the matter before the House of Commons, and the two surviving officers were promoted and all the survivors received pecuniary compensation for their losses.
Napier was much affected by the death of the Duke of Wellington in September 1852. He was one of the general officers selected to carry banderoles at the funeral. He watched at the death-bed of his brother Charles in August 1853, and succeeded him in the colonelcy of the 22nd regiment. He had been promoted lieutenant-general on 11 Nov. 1851. On 13 Oct. 1853 followed the death of his brother Henry, captain in the royal navy. Napier solaced himself in his grief by preparing for the press the book which Charles had left not quite completed, viz. ‘Defects, Civil and Military, of the Indian Government,’ and by commencing the story of Charles's life, which he published in 1857. The work is that of a partisan.
During 1857 and 1858 Napier became increasingly feeble. He had long been unable to walk. In October 1858 he had a violent paroxysm of illness, and, although he rallied, he never recovered. He was promoted general on 17 Oct. 1859, and died on 10 Feb. 1860. He was buried at Norwood. His wife survived him only six weeks. She was a woman of great intellectual power, and assisted her husband in his literary labours.
His only son, John, was deaf and dumb, but held a clerkship in the quartermaster-general's office at Dublin. His second surviving daughter married in 1836 the Earl of Arran. The third daughter died on 8 Sept. 1856. In 1846 his fifth daughter married Philip Miles, esq., M.P., of Bristol. His youngest daughter, Norah, married, in August 1854, H. A. Bruce, afterwards Lord Aberdare and Napier's biographer.
Napier was noble and generous by nature, resembling his brother Charles in hatred of oppression and wrong, in a chivalrous defence of the weak, and a warm and active benevolence. He was an eloquent public speaker, but sometimes formed his judgments too hastily. He had a great love of art, and was no mean artist. His statuette of Alcibiades, in virtue of which he was made an honorary member of the Royal Academy, received the warm praise of Chantrey. When at Strathfieldsaye, obtaining information from the Duke of Wellington for his ‘History,’ he copied some of the paintings very successfully, and made two very fine paintings of the duke's horse Blanco. The activity of his mind to the very last was extraordinary, considering the helpless state of his body. He was one of the first to advocate the right of the private soldier to share in the honours as he had done in the dangers of the battlefield. On the south side of the entrance to the north transept of St. Paul's Cathedral is a statue by G. G. Adams of Napier, with the simple inscription of his name, and the words, ‘Historian of the Peninsular War.’ On the other side of the entrance is a statue of his brother Charles. A portrait in crayons, by Mr. G. F. Watts, R.A., is in the possession of Napier's son-in-law, Lord Aberdare.
Napier's chief works are: 1. ‘History of the War in the Peninsula and in the South of France from the year 1807 to the year 1814,’ including answers to some attacks in Robinson's ‘Life of Picton’ and in the ‘Quarterly Review;’ with counter-remarks to Mr. D. M. Perceval's ‘Remarks,’ &c.; justificatory pieces in reply to Colonel Gurwood, Mr. Alison, Sir W. Scott, Lord Beresford, and the ‘Quarterly Review,’ 6 vols. London, 1828–40, 8vo; 2nd edit.,