London in 1825, the Duke of Wellington consulted Rothschild as to the best means of meeting the crisis, and his advice was followed by Lord Liverpool's government. In 1828 he was commissioned by Wellington to send a sum of money to Dom Miguel, who was just appointed regent of Portugal in behalf of his niece, Donna Maria. Rothschild was doubtful of Dom Miguel's intention of honestly respecting his niece's claim to the throne or of governing the country constitutionally in accordance with the wishes of England and France. Instead, therefore, of forwarding the money to the regent, Rothschild sent it to Sir Frederick Lamb, the British minister at Lisbon. When the ship with the gold arrived at its destination, Dom Miguel had violently seized the throne in defiance of the powers, and the money was restored to the English government. In 1835 Rothschild and his brother-in-law Montefiore contracted with the English government to raise 15,000,000l. to be applied to the compensation of slave-owners in the West Indies. Doubts were freely expressed as to the advisability of undertaking so large a loan in time of peace, but Rothschild's confidence in the wisdom of the operation was fully justified by the event, for the slave-owners largely invested in consols the moneys they received.
Such a series of operations impressed the public imagination. Byron, writing in 1823 in ‘Don Juan’ (canto xii. st. v. and vi.), in reference to the collective power of Rothschild and Baring, declared that
Is not a merely speculative hit,
But seats a nation or upsets a throne.
Besides floating foreign loans, Rothschild dealt in all existing stocks, and often purchased largely of securities which appeared to be unsaleable. He was often employed, too, in converting stocks bearing a high rate of interest into those bearing a lower rate, and he operated extensively and with singular judgment in bullion and foreign exchanges. In 1824 he took a leading part in the formation of the Alliance Insurance Company, but he generally avoided connection with joint-stock companies. His most successful mercantile enterprise was in 1832, when his eldest son, Lionel, who was in Madrid on business with the bank of Spain, purchased by tender of the Spanish government the whole product of the Spanish quicksilver mines for a term of years. The Rothschilds already held the control of the Idria mines from the Austrian government, and they thus obtained a monopoly of mercury.
Rothschild began business with a firm belief in the stability of England's resources. He never doubted that her triumph over Napoleon would ultimately be complete. Faith in England's power was thus the dominant note of his conduct of business. He formed his decisions rapidly, and his judgment, on which smaller capitalists placed implicit reliance, was rarely at fault. His memory and calculating power were exceptional, and without taking any notes he could dictate to his clerks with perfect accuracy an account of all the transactions undertaken during the day.
Rothschild took a leading part in the efforts to abolish the political disabilities of English Jews. With Sir Moses Montefiore he prepared a petition to the House of Commons in 1829. He entertained supporters of the projected measure at his house in Piccadilly, and had frequent interviews with Wellington, Lyndhurst, Brougham, and other statesmen. In 1834 he ‘advised Wellington to form a liberal government and consent to some reforms,’ telling him ‘that he must go with the world, for the world would not go with him’ (Montefiore Diaries, ed. Loewe, i. 93–4).
Rothschild removed in middle life from his business premises in New Court to Stamford Hill, and afterwards to No. 107 Piccadilly; he acquired a country house at Gunnersbury in the year of his death, but never lived there. He died on 28 July 1836 at Frankfurt, whither he had gone to attend the marriage of his eldest son. Montefiore was with him at his death (ib. p. 103). His body was brought to England, and buried in the Jewish cemetery at Mile End on 8 Aug. The funeral was attended by most of the foreign ambassadors. His will, a very lengthy document, was printed in the original German in Von Treskow's ‘Biographische Notizen’ (Leipzig, 1837), and in English in the ‘Annual Obituary’ for 1837. He gave each of his seven children 100,000l., but left the residue of his estate at the disposal of his widow. A portrait of him was engraved by Penny, and a characteristic whole-length was etched by Dighton. He married, on 22 Oct. 1806, Hannah, third daughter of Levi Barnet Cohen, a London merchant. Her sister married Sir Moses Montefiore. She is said to have had great business capacity, and her husband left instructions that his sons were to engage in no undertaking of moment without her consent. She was also widely known by her munificent charities; she died on 5 Sept. 1850, and was buried beside her hhusband. The issue of the marriage was four sons and