Mandeville, whose mother ran off with a footman before formally separating from his father in 1813, entered the navy direct from Eton in 1812, but he was later reported to be unhappy in the profession.
He shared his mother-in-law’s Evangelical zeal and supported a number of Protestant societies, but his abiding passion was the exegesis of apocalyptic texts. He corresponded with clergy and laymen of various denominations, including Henry Drummond and Edward Irving. He regularly attended their conferences for the study of unfulfilled prophecy at Albury Park, Surrey, but it is uncertain whether he became a member of their Holy Catholic Apostolic Church.
Lord Mandeville is truly sublime and soul-subduing in the views he presents. I observed a curious thing, that while he was reading a paper on Christ’s office of judgement in the millennium everybody’s pen stood still, as if they felt it a desecration to do anything but listen.
M.O.W. Oliphant, Edward Irving, 273.
He had already ventured into print on behalf of the Continental Society; but it was his elaborate essay On the New Covenant, published that year in Morning Watch, which established his reputation as an amateur theologian.
In September 1824 it was reported that Mandeville, who was described as ‘a liberal’, would offer for county Armagh at the next general election, but nothing came of this.
Pray do not give way to such mistaken feelings of religion, but consider how much your own importance and character are at stake by your representing the county ... I think on reflection your scruples about the people getting drunk must vanish. If your notions are correct, the whole 600 [sic] Members ... must be culpable, and in fact according to such ideas we ought to have no Parliament.
Huntingdon, Bedford and Peterborough Gazette, 9 July, 24 Sept.; Manchester mss 21a/8, Maltby to Lady Mandeville, 28 Sept., Montagu to Mandeville, 9 Dec. 1825.
Shortly afterwards Mandeville changed his mind again and, much to Lord Frederick’s approval, took up the cause ‘with spirit and energy’, though he retained his misgivings about entertaining the freeholders.
Mandeville was excused further attendance on an election committee, 20 Feb. 1827, on account of the death of his youngest sister. He voted against Catholic relief, 6 Mar. He was granted three weeks’ leave, 27 Mar. In May he was elected as the first president of the non-political British Society for Promoting the Religious Principles of the Reformation.
At the general election of 1830, when he topped the poll after a short contest, Mandeville claimed to be motivated by a desire to ‘let the oppressed go free’ and said he would support ministers only when he judged them to be right.
Although he was opposed to the reform measure, it was not because he wished to perpetuate a system of corruption, but he could not think that House of Commons very corrupt which had voted out two different administrations, and believed that the present distress did not arise from misrepresentation, but from taxation.
He dismissed the reform bill as ‘not a renovation, but a revolution of the constitution’. Pressed to be more explicit, he conceded that £10 householders in Huntingdon might reasonably be enfranchised; but with respect to the country at large, he said that he feared the augmentation of Catholic power and that Daniel O’Connell* would be able to nominate as many Members ‘as the borough mongers are said to return’.
Mandeville presented petitions against the Maynooth grant from Scotland and Ireland, as well as constituency petitions against slavery and the coal duties, 23 June 1831. He denounced the grant and questioned the propriety of all such subsidies in the wake of emancipation, 19 July. Having been criticized by O’Connell on account of the bigoted wording of the June petitions, he assured the House, 20 July, that the petition he was about to present contained no inflammatory language. He spoke and voted against the grant, 26 Sept., when, aware that he was an easy target for derision from the treasury benches, he declared, ‘I would rather subject myself even to their ridicule than I would say or do anything which could have the effect of hurting the church of which I am a member’. He divided against the second reading of the reintroduced reform bill, 6 July, and in the opposition minorities for using the 1831 census as a basis for disfranchisement, 19 July, and against the partial disfranchisement of Chippenham, 27 July. He voted against the bill’s passage, 21 Sept. He was granted three weeks’ leave to attend to urgent business, 29 Sept. He was absent from the division on the second reading of the revised reform bill, 17 Dec. 1831. On the 28th he was prominent at the Armagh county meeting which addressed the king on the threatened state of the Protestant interest in Ireland.
Mandeville, who continued to sit for Huntingdonshire until 1837 and succeeded to the dukedom in 1843, was a ‘consistent Tory’ and active promoter of the Protestant cause throughout his life. He died in August 1855.
