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Cavendish, William, fourth duke of Devonshirefree

(bap. 1720, d. 1764)
  • Karl Wolfgang Schweizer

Cavendish, William, fourth duke of Devonshire (bap. 1720, d. 1764), prime minister, was baptized at St Martin-in-the-Fields, Westminster, on 1 June 1720, the eldest of the four sons of William Cavendish, third duke of Devonshire (1698–1755), politician and landowner, and his wife, Catherine (c.1700–1777), the eldest daughter of John Hoskins, of Oxted, Surrey, steward to the duke of Bedford. Styled marquess of Hartington from 1729, when his father succeeded to the dukedom, he was probably educated at home before undertaking the grand tour to France and Italy in 1739–40, accompanied by his tutor, the Revd Arthur Smyth.

The Cavendish family was at the heart of the whig party that had dominated politics since the Hanoverian succession, and a career in politics was the inevitable destiny for Hartington, as heir to one of the premier dukedoms in the country. As soon as he came of age he was elected to the House of Commons in May 1741 as MP for Derbyshire, the family seat, and adopted his father's allegiance to the prime minister, Sir Robert Walpole. After Walpole's resignation in 1742 Hartington sided with Walpole's political heirs, the Pelham faction, led by Henry Pelham and his brother the duke of Newcastle, and strongly supported their attempts to fashion a viable administration over the next four years. Pelham highly valued both his abilities and his loyalty; as he informed Devonshire in 1743, Hartington was 'our mainstay amongst the young ones, of themselves liable to wander' (Sedgwick, 538).

On 27 March 1748 Hartington married Lady Charlotte Elizabeth Boyle, Baroness Clifford of Londesborough (1731–1754), the third yet only surviving daughter of Richard Boyle, third earl of Burlington (1694–1753), and his wife, Dorothy Savile (1699–1758). The match had been planned during the couple's childhood, although Hartington's mother, who had married for love, refused to approve the arranged marriage and remained estranged from her son and his family for the rest of her life. Despite her fears, the marriage proved to be happy and loving, albeit short, for Charlotte died six years later, on 8 December 1754 at Uppingham. They had four children: William Cavendish, later fifth duke of Devonshire (1748–1811); Dorothy (1750–1794), who married William Bentinck, third duke of Portland; Richard (1752–1781), MP for Lancaster and then Derbyshire; and George (1754–1834), MP for Knaresborough, then Derby, who became first earl of Burlington of the second creation in 1831. It was certainly a politically advantageous marriage, as Charlotte's inheritance on her father's death in 1754 included vast estates in Yorkshire and Ireland, as well as electoral interests over the two parliamentary seats at Knaresborough and the Irish parliamentary constituency of Lismore Town. Burlington's valuable art collection, his villa at Chiswick, and Burlington House in Piccadilly also passed into the Devonshire family.

With his political standing enhanced by his marriage, Hartington took his seat in the Lords in his father's barony of Cavendish on 13 June 1751, which enabled him to accept the mastership of the horse and a cabinet seat from Pelham; he had earlier declined the governorship of the new prince of Wales, the future George III. He was appointed to these offices and sworn of the privy council on 12 July. Following Pelham's death in 1754 he adhered closely to Newcastle, who appointed him lord lieutenant of Ireland in March 1755, in succession to the first duke of Dorset. He was ideally qualified for the post, not only by his landed and political interests in Ireland, but also by his family connections with some of the principal political players in the country, namely Henry Boyle (his late wife's uncle) and William and John Ponsonby (both of whom were married to his sisters). Crucially, his closeness to Henry Fox at Westminster made him acceptable to Fox's brother-in-law, the earl of Kildare, who opposed the Ponsonby faction. Furthermore his father had been a popular lord lieutenant in Ireland from 1737 to 1745, and Hartington's own easy-going temperament seemed suited to the difficult job of reconciling the Irish patriot factions, led by Boyle and Kildare, with the Dublin Castle administration, headed by George Stone, archbishop of Armagh, and his Ponsonby allies.

Hartington arrived in Dublin in May 1755 to find Boyle and Kildare demanding Stone's removal from office as chancellor of exchequer and the restoration of offices to Boyle and his supporters. A common source of strife was the appointment of lords justice to govern Ireland in the absence of the lord lieutenant, which Hartington deliberately side-stepped by resolving to remain in Ireland. He outlined his policy of reconciling the rival factions in a letter to Newcastle, dated 4 October 1755: 'My scheme is if possible to govern this country without a party and make those that receive favours from the Crown think themselves obliged to it and not to their party here' (J. C. D. Clark, 282). In spring 1756 he made a bolder attempt to neutralize the friction between the patriots and the Dublin Castle administration when in March he procured Boyle's resignation as speaker of the Irish Commons for the price of a pension and a peerage, and replaced him with John Ponsonby. He followed this up by appointing Kildare sole lord justice in May and by persuading Stone to withdraw his claim to be considered as a lord justice. Hartington left Ireland in the autumn, having won a tactical victory by wrong-footing the patriots and by adopting an 'anti-party ideology'. Though it proved only a temporary success in breaking the Irish undertakers' dominance, his policy paved the way for the decisive viceroyalty of the fourth Viscount Townshend in the 1760s.

On 5 December 1755 Hartington succeeded on his father's death as fourth duke of Devonshire. He returned to England in October 1756 at a time of conflict with France and political instability at home. Fox's resignation that month triggered the end of Newcastle's administration, which had been worn down by military failures, such as the loss of Minorca earlier that year and the French capture of Fort Oswego on Lake Ontario. Pending a more permanent arrangement, whereby William Pitt could be reconciled with Newcastle, George II summoned Devonshire to form an interim ministry to avert government collapse and to manage the war with France. On 6 November, Devonshire was appointed first lord of the Treasury and Pitt succeeded Fox, who had been unable to form a viable ministry, as secretary of state for the south. The virtues of tact, affability, and honesty that Devonshire had used to good effect as lord lieutenant were now needed to bring about the desired reconciliation between Pitt and Newcastle; as Newcastle commented on 13 November, Devonshire was the 'great engine, on whom the whole turns at present' (J. Clark, 287). As in Ireland, Devonshire attempted to utilize Pitt's patriot credentials to create a ministry that was devoid of party allegiances but as a consequence lacked a secure political base. Despite the notorious court martial and execution of Admiral Byng, which dominated politics early in 1757, there were definite achievements. It was under this administration that America was set forth as a strategic priority, a militia for home defence was established, a continental army was assembled, and naval raids against the French coast were organized; however, these policies owed more to Pitt than to Devonshire.

As predicted, the DevonshirePitt ministry proved short-lived, and it was fatally damaged in April 1757 when Pitt resigned, along with his cousin Temple. After two months of protracted negotiations the NewcastlePitt coalition succeeded to office on 29 June, a coalition that led Britain to victory over France. Although Devonshire had played a vital role in forging the coalition, he was far from complacent about its chances of survival. He wrote to Lord Mansfield on 20 June of the proposed ministry:

the plan is undoubtedly the best that could be formed, the only difficulty will be to make it hold … the utmost of my abilities are to see an administration settled that will endeavour with firmness and unanimity to extricate this country out of the dangerous situation it is in at present.

J. Clark, 442

With no desire for high office, Devonshire became lord chamberlain in the coalition but retained a seat in the inner cabinet, where his integrity, family standing, and friendship with leading whigs allowed him to calm the rancour of party politics and personality differences. This was especially important after the accession of George III in October 1760 and the advent of his mentor, Lord Bute, whose rapid advancement threatened to undermine whig hegemony and destabilize governmental politics. Throughout 1761 and 1762, during the peace negotiations with France, Devonshire was a key factor in maintaining the ministerial harmony necessary for achieving peace. During the momentous months from September 1759 to October 1762 he kept a diary which offers keen insights into the decision-making process and general diplomatic affairs of the time. Fascinatingly, Devonshire's diary reveals his unalterable view that Britain should be governed by an aristocratic oligarchy while at the same time testifying to his own resolution to remain an onlooker rather than a principal actor in the political arena.

When Newcastle resigned in May 1762 Devonshire did not follow him out of office but showed his solidarity by refusing to attend cabinet. This anomalous situation, whereby he retained his office yet absented himself from the business of government, could not be tolerated for long. Disagreement with Bute over the final peace treaty led to his resignation as lord chamberlain on 28 November 1762. George III expressed his extreme displeasure at his conduct a few days later when, with his own pen, he struck Devonshire's name from the list of privy councillors, a rare gesture that emphatically ended Devonshire's political career. Devonshire took part in the opposition to the Cider Tax Bill that brought about Bute's downfall in April 1763. Perhaps as a punishment, Devonshire was further disgraced when in October 1764 the king dismissed him as lord lieutenant of Derbyshire, an office that had been held continuously by the Cavendishes since George I's accession. His last months were spent at Spa, Germany, in a state of deteriorating health. He died there on 2 October 1764, aged forty-four, and was buried next to his wife in All Saints', Derby.

Devonshire was a man of solid if not outstanding abilities. He was endowed with the qualities—devotion to friends and duty, patriotism, and unswerving integrity—which made him the ideal sounding board and factotum among the prominent politicians of his day. Unlike Pitt or Fox he lacked a brilliant mind, and his diary provides evidence of devotion to king, country, and duty rather than quickness of intellect. A political broker rather than a leader, he exploited his personal popularity and family prestige to mediate between the factious and egotistical individuals who dominated Dublin and Westminster politics in the 1750s and early 1760s.


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  • Chatsworth House, Derbyshire, corresp. and papers
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  • W. Hogarth, oils, 1741, Yale U. CBA
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  • A. Ramsay, oils, 1759, NPG
  • attrib. G. Knapton, oils, Hardwick Hall, Derbyshire
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R. Sedgwick, ed., , 2 vols. (1970)
, Church of Jesus Christ of the Latterday Saints
Camden Society
Historical Journal