Initially destined for a military career, Mildmay’s marriage to a Barings heiress propelled him to a top seat in the family’s mercantile house, where his ‘natural timidity’ as a speculator soon became ‘a constant source of complaint’.P. Ziegler, The Sixth Great Power: A History of One of the Greatest Banking Families, the House of Barings, 1762-1929 (1988), 120, 126. His fellow partners heaved a sigh of relief when he finally secured election to the Commons as MP for Southampton. A loyal Conservative but fierce critic of Peel’s repeal of the corn laws, his principled refusal to take up ‘No Popery’ pledges cost him his seat in 1847, by when he appeared to be suffering from a nervous breakdown.A. Temple Patterson, A History of Southampton 1700-1914 (1966), ii. 63; Ziegler, Barings, 126.

The sixth son of a Tory baronet who had purchased an electoral interest at Winchester, Mildmay (as he was generally known) was born into one of Hampshire’s leading political families. Following the death of the baronet in 1808, Mildmay’s mother Lady Jane Mildmay had assumed control of the family’s political interest, returning his elder brothers Sir Henry Carew St. John Mildmay (1787-1848) and Paulet St. John Mildmay (1791-1845) in succession for Winchester, which they both represented as Whigs.HP Commons, 1790-1820, ii. 193-95, v. 87-91; HP Commons, 1820-32, ii. 458-61, vii. 9-11. Mildmay and some of his younger brothers, however, adopted their father’s Tory line in politics, but as younger sons ended up taking up positions in the church or the military. After attending Winchester College Mildmay joined the Coldstream guards and served briefly in the Peninsular war. By 1821 he was a captain serving with the 35^th infantry regiment.H. Mildmay, A brief memoir of the Mildmay family (1913), 216.

In 1823 Mildmay made ‘one of the few rich marriages of the family’.Mildmay, Mildmay Family, 216. His wife, a ‘Baring heiress’, was the eldest daughter of Alexander Baring MP, a partner in Baring Brothers and Co., the leading mercantile house widely regarded as the world’s ‘the sixth great power’. On his retirement from the bank in 1828 Baring made Mildmay a partner, despite him having ‘no experience of mercantile matters’.Ziegler, Barings, 93. ‘He let his son-in-law enter it, [who] until his admission into this partnership had been a brevet captain’, noted one astonished observer.V. Nolte, Fifty years in both hemispheres: reminiscences of the life of a former merchant (1854), 287. Alongside Thomas Baring MP (1799-1873) and Joshua Bates, Mildmay became ‘one of the ruling triumvirate at Barings’, on the basis of which he was also made a director of the Bank of England.J. Dilts, The Great Road: the building of Baltimore and Ohio (1996), 249.

The appointment was not a success. Mildmay’s nervousness about speculating with millions of pounds made him ‘quite unfit to run the bank’, and his partners at Barings were soon treating him ‘with affectionate contempt’. ‘His punctuality and attention to business deserve great praise’, remarked Bates, ‘but he suffers from weak nerves and having had but little experience his natural timidity is thereby heightened’.Baring mss, citied in Ziegler, Barings, 120. It was almost certainly Mildmay who was responsible for the company’s embarrassing volte face over the slavery compensation loan to the British government in 1835. Mildmay was present at the crucial meeting of leading bankers with the chancellor of the exchequer Spring Rice that July, but the proposed syndicate later collapsed due to the sudden withdrawal of Barings, enabling the Rothschilds to monopolise what became the largest loan ever provided to the UK.PP 1835 (463), li. 1; N. Draper, The Price of Emancipation: Slave-ownership, compensation and British society at the end of slavery (2010), 108-9. As if to rub it in, Mildmay was subsequently among the Baring partners who unsuccessfully lodged a counter-claim for compensation for 64 slaves owned by a debtor in British Guiana.Draper, Price of Emancipation, 246; http://www.ucl.ac.uk/lbs/claim/view/8556. In 1837 he acquired a spacious mansion in Berkeley Square from the late earl of Darnley, which allowed him to entertain on a grand scale.Morning Post, 10 Feb. 1837.

Mildmay’s first two attempts to enter Parliament ended in failure. In 1835 he stood for Maldon with the backing of his younger brother Carew (1800-78), rector of nearby Chelmsford, citing his support for a repeal of the malt tax and adherence to the ‘same principles’ as his father, who had ‘lived and died a staunch Tory’. He was defeated in third place.Morning Post, 6 Jan. 1835; Essex Standard, 9 Jan. 1835; Ipswich Journal, 10 Jan. 1835. In May that year he agreed to stand for a by-election in Stroud after he was recommended to local Tories by the Carlton Club, but quickly transferred his attention to an opening at Hull, where his mercantile connections and support for the ‘shipping interest’ would curry more favour.Morning Chronicle, 15 May 1835. Denouncing the Whigs for ‘courting the Popish and Radical popularity of the day’, he made much of their abortive attempt to disfranchise freemen in the municipal reform bill. He was narrowly defeated by just five votes.Morning Post, 18 June 1835; Hull Packet, 26 June 1835.

Mildmay eventually secured election in 1842 after a protracted candidacy at Southampton, first for an anticipated vacancy that never took place and then in the double by-election that followed the unseating of both the sitting Tories for bribery. His family’s local status featured prominently throughout his campaign, managed by the borough’s irrepressible Tory patron John Fleming MP, but it was his role as ‘head of the most extensive mercantile house in the world’ and command of ‘all that commercial and shipping influence ... so desirable in the representative of a port’ that secured his return at the top of the poll. He also agreed to contribute at least £5,000 ‘to secure his election’.Hampshire Advertiser, 8 Jan., 16 Apr., 7 Aug. 1842.

Mildmay’s Commons’ duties inevitably curtailed his involvement at Barings, though probably not enough for his partners, who were finding him ‘increasingly a liability’.Ziegler, Barings, 126. A regular attender, he gave silent support to Peel’s ministry in the lobbies on most major issues, including its lowering of the import duties on Canadian wheat (1843) and West Indian sugar (1844), its reform of the Bank of England (1844) and permanent endowment of the Irish Catholic seminary at Maynooth (1845). However, he remained a firm supporter of the corn laws, voting steadily against opposition motions for their repeal or reduction. In his first known speech, 18 Aug. 1843, he protested against the restrictions on sureties for debt imposed by the slave trade suppression bill, as they would ‘inflict a most serious injury’ on English merchants. Describing it as ‘a bill to suppress the foreign colonial trade of the empire’, he threatened to move a hostile amendment, but desisted when Peel objected.Hansard, 18 Aug. 1843, vol. 71, c. 936. He was less obliging in his next major intervention, against the second reading of Peel’s controversial bill to repeal the corn laws, 27 Mar. 1846. Denouncing Peel’s ‘total annihilation of all protection to native produce’ at a time when corn was so abundant and cheap abroad, he accused the premier of deliberately exploiting the Irish famine and delaying relief, in order to ‘justify the proposal of a total abolition’ when other alternatives were available.Hansard, 27 Mar. 1846, vol. 85, cc. 208-13. He evidently hit his mark, for Peel immediately responded by taking issue with his notion of ‘a sliding-scale for three years and then a fixed duty’, insisting that it would be ‘rejected with scorn—laughed at—scouted’ by the agricultural body.Hansard, 27 Mar. 1846, vol. 85, c. 228. He was in the hostile minorities against repeal, 27 Mar., 15 May 1846, but unlike many Protectionist malcontents rallied to Peel on the renewal of the Irish coercion bill, 25 June 1846, the issue that brought his ministry down. When the incoming Russell administration re-introduced the coercion bill, he was initially ‘prepared to support’ them, but after hearing that they considered it a ‘bad measure’, which they were only passing due to the lack of time, he demanded to know why it was that they had ‘not hesitated, late as the session was, to propose a sugar duties bill’, which would further undermine the West India interest.Hansard, 10 Aug. 1846, vol. 88, c. 593. Thereafter he steadily opposed the Liberal ministry in the lobbies, prior to the 1847 dissolution.

At the 1847 general election Mildmay offered again for Southampton, where the local party was split between Peelites and Protectionists, many of whom had been ‘offended’ by his support for the Maynooth grant. Invited by a Tory meeting to ‘pledge’ his opposition to further Catholic concessions, he categorically refused and left the field, explaining that he ‘differed’ with a ‘very influential portion’ of his friends over the treatment of ‘our Catholic fellow citizens’.Morning Chronicle, 28 July, 31 July 1847; Temple Patterson, Southampton, ii. 63. A subsequent bid to stand for Pontefract in 1852 came to nothing.Manchester Times, 3 July 1852.

By 1847 Mildmay, whose first wife Anne Baring had died tragically in 1839 ‘as the result of her clothes catching fire’, had been ‘eased out’ of Barings Bank.N. Smith, The Letters of Sydney Smith (1953), ii. 645; Ziegler, Barings, 164. Writing to the other partners, 10 Aug. 1847, his brother-in-law Francis Baring had reported that Mildmay ‘is to be pitied, for his mind is in a morbid state’.Baring mss, cited in Ziegler, Barings, 126. As a ‘sop’ his second son Henry Bingham (1828-1905) was taken on in 1845 and brought into the counting house in 1853.Ziegler, Barings, 128, 164.

Mildmay died later that year at his home in Berkeley Square, where he lived with his second wife, who was twenty years his junior, his two adult sons from his first marriage, two young daughters from his second, and a dozen servants.Gent. Mag. (1853), ii. 326. The servants comprised a housekeeper, six maids, two butlers, two footmen and a Swiss governess: 1851 census. He left personal estate valued at £300,000. His eldest son Humphrey Francis (1825-66) followed him into Parliament as MP for Herefordshire, 1859-65, but like Mildmay’s elder brothers adopted a Liberal line in politics. Letters from Mildmay to his banking partners are held by the Baring Archive, London.Baring mss, HC.1.20.1 (www.baringarchive.org.uk).