Beresford, John Claudius (1766–1846), politician and banker, was born 23 October 1766 in Dublin, third son among nine children of John Beresford (qv), commissioner of revenue and son of Marcus Beresford (1694–1763), 1st earl of Tyrone, and Anne Constantia, daughter of the comte de Ligondes of Auvergne, France. Educated at Dr Stokes's school and TCD, he graduated BA (1787). Through his father's influence he was elected MP for Swords, Co. Dublin (1790–97), and he later represented Dublin city (1797–1800). In keeping with the Beresford tradition he amassed a series of lucrative sinecures: storekeeper for the inland department (1783–1802), registrar general of tobacco (1784–99), inspector general of exports and imports in Dublin port (1796–9), and taster of wines (1798–1802); he was also an Irish privy councillor, a wide streets commissioner (1790–1846), agent to the London Society, Londonderry, vice-president of the Marine Society of Ireland, a member of the Ballast Board, governor of Steevens' Hospital and of the Foundling Hospital, and a trustee of the Irish linen board (1802). He was a senior partner in one of Ireland's most important private banks, Beresford & Co. (founded 1793), which between 1799 and 1803 issued banknotes to the value of about £700,000 a year – more than any other bank in Ireland. A prominent figure in Dublin's commercial and political life, in 1797 he received the thanks of the Guild of Merchants for his efforts in quashing a bill regulating the coal trade.
In parliament he opposed parliamentary reform and catholic emancipation throughout the 1790s, and advocated strong measures to deal with disaffection. Described as ‘intemperate in his politics, though unimpassioned in manner’ (McDougal, 160), he was governor of the Aldermen of Skinners' Alley, an influential loyalist society founded in 1795 to support the protestant ascendancy. Before the rebellion of 1798, he was said to have expressed a wish for it to break out soon, so that the United Irishmen could be speedily crushed. Captain commandant of the Dublin merchants' yeomanry corps, dubbed ‘Beresford's bloodhounds’ during the 1798 rebellion for their zeal in hunting down rebels, he allegedly took a prominent part in flogging suspects in the family riding school in Marlborough St., Dublin, in 1798. Ever afterwards he was loathed by rebel sympathisers, but the story that they burned his banknotes to ruin him is apocryphal. He was elected to the commons secret committee to investigate the rebellion and he later unsuccessfully attempted to bring in bills to confiscate the property of all those convicted of high treason and to deprive of the franchise all those who sympathised with the rebellion. An active Orangeman, he was general secretary of the Orange lodges of Ireland (1799–1800). Unlike the rest of his family, he opposed the union and voted against it, citing the anti-union views of his Dublin constituents and his own belief that the measure would harm Dublin commercially. He was, however, reluctant to push his opposition too far and published appeals to his fellow Orangemen for neutrality on the issue (1799, 1800). To relieve the government from dismissing him, he resigned his customs places in 1799. Beresford argued strongly against the financial provisions of the union, but his proposal for a reduction in the Irish share of future imperial expenditure was soundly defeated (25 February 1800). After the passing of the union he signed a declaration acquiescing in the measure and pledging to reconcile his constituents to it.
He represented Dublin city at Westminster (1801–4), topping the poll each time he stood for election. During the 1802 election the anonymous author of The city candidates: or a plumper for John Claudius Beresford (1802) urged catholics to vote for Beresford because he was a ‘sound Orange’ rather than a bigot, who opposed catholic relief on civil rather than religious grounds. During this election he resigned his remaining sinecures to placate his constituents. He succeeded his father as MP for Co. Waterford (1806–11) and became the Beresfords' chief political negotiator. A member of the Irish currency and finance committees, he attempted to extract the maximum patronage from government and proved an unreliable ally of both the Grenville (1806–7) and Portland (1807–9) administrations. He had interests in several Dublin businesses, and engaged in extensive land speculation on the city's northside, but managed his affairs badly. Beset by financial difficulties from about 1810 – partly caused by the post-union slump in land values – he resigned from the bank and parliament as a bankrupt. (In 1808 he had been joined as a partner by Benjamin Ball (1762–1825) and others, and from 1810 the bank continued as Ball & Co.)
Despite his notorious reputation, in private life he appears to have been good-natured and non-sectarian, a generous contributor to various charities, and liked by many of his fellow citizens. An alderman of Dublin corporation from 1808, he served as lord mayor of Dublin (1814–15) and was noted for his lavish hospitality. During these years he was regularly pilloried by Walter Cox (qv) for his ultra-loyalist politics, property speculations, and financial difficulties. After 1815 he largely withdrew from public life, although he campaigned for his cousin Lord George Beresford (qv) in the celebrated 1826 election in Co. Waterford when the county's forty-shilling freeholders defied the Beresfords. His intervention was counterproductive: he was received coldly by his former constituents, and the Catholic Association used his notorious record in 1798 to paint the Beresfords as violent bigots. He was conferred with an MA by TCD (1832). His main Dublin residences were 8 Buckingham St., Summerhill (until c.1812) and afterwards at Goose Green, Drumcondra. He died 20 July 1846 at his house at Glenmoyle, Co. Londonderry.
He married (3 March 1795) Elizabeth McKenzie, daughter of Archibald Menzies of Culdaress, Perth, Scotland; they had one son, also named John Claudius (d.s.p. 1866), and four daughters.