Correspondence of William Cavendish, 4th Duke of Devonshire

This collection of correspondence largely comprises letters to and from William Cavendish, 4th Duke of Devonshire (1720-1764) and members of his family and his associates between December 1755 and September 1764. The most prolific years of correspondence are the earlier ones. This correspondence begins once the 4th Duke inherited the dukedom from his father and ends about a month before his death. The correspondence illuminates his roles as politician and courtier (Lord Lieutenant of Ireland, First Lord of the Treasury, Lord Chamberlain); brother, son and father; local landowner (and Lord Lieutenant of Derbyshire) in Derbyshire, and absentee landowner in Ireland and Yorkshire.

As well as correspondence, the collection includes other material that would have been enclosed with letters, such as minutes of meetings; memoranda; receipts; printed letters; and newspaper cuttings (from the London Gazette).

The letters cover political, social and personal matters of: the 4th Duke and wider Cavendish family; Kings George II and III; Prince Ferdinand, Duke of Brunswick; Prince William, Duke of Cumberland; Princess Amelia; other royals; prime ministers; military personnel; privy councillors; members of the royal court; British, Irish, and other European politicians; ambassadors; government spies; architects; actors; poets; clergymen; lawyers; judges; educators; servants; land agents; and many members of the aristocracy and gentry.

The main correspondents with the 4th Duke in this collection are: Thomas Pelham-Holles, 1st Duke of Newcastle; Henry Fox; Wellbore Ellis, 1st Baron Mendip; Lord Frederick Cavendish; Henry Seymour-Conway; Sir Anthony Abdy; John Stuart, 3rd Earl of Bute; and William Ponsonby, 2nd Earl of Bessborough.

Other correspondents include: James Fitzgerald, 1st Duke of Leinster; Robert, 1st Viscount Jocelyn; John Bowes; Lord George Cavendish; Sir William Fitzherbert of Tissington; Dorothy Boyle (née Savile), Countess of Burlington; Katherine Cavendish (née Hoskins), Duchess of Devonshire; John Ponsonby; Sir Robert Wilmot; Thomas Edwards; William Pitt, 1st Earl of Chatham; Philip Yorke, 1st Earl of Hardwick; Prince Frederick, Duke of Brunswick; Thomas Coke, 1st Earl of Leicester; James Ralph; Arthur Rochfort; David Garrick; Alexander Barker; Anthony Coghlan; Sir George Howard; Joseph-Marie-François-Justin de Viry, comte de Viry; Charles Watson-Wentworth, 2nd Marquess of Rockingham; Lord John Cavendish; Dr Richard Newcome; and Mary Watson-Wentworth, Marchioness of Rockingham.

Women writers are underrepresented in this collection less than ten percent of the letters are written by women and, of these, most were from women to whom the 4th Duke was related (his mother, sisters and mother-in-law). The exceptions include: Mary Watson-Wentworth (née Bright), Marchioness of Rockingham; Amalie Sophie Marianne von Wallmoden, Countess of Yarmouth; Lady Mary Coke (née Campbell); Alicia Maria Wyndham (née Carpenter), Countess of Egremont; Mary Howard (née Blount), Duchess of Norfolk; Anne FitzRoy, Duchess of Grafton; and Princess Amelia. The topics of these letters vary from social arrangements to meetings concerning political matters and recommendations for vacant commissions.

The collection does include letters neither written to nor from the 4th Duke. In most cases, these letters were enclosures sent with correspondence addressed to the 4th Duke. The exceptions to this are the letters from his brother, Lord Frederick Cavendish, to Prince William, Duke of Cumberland.

Themes, historical events and topics covered thoroughly in the correspondence include:

- The death of the 3rd Duke of Devonshire correspondence includes condolences from political friends and family; arrangements for the funeral; and mourning liveries for the 4th Duke s household in Dublin where the 4th Duke remained (early 1756);

- The military career of Lord Frederick Cavendish as soldier and as Lord of the Bedchamber and aide-de-camp to Prince William, Duke of Cumberland, especially referencing battles and camps on the Continent (1756-1763);

- The 4th Duke s relationship with his mother, Katherine Cavendish (née Hoskins), Duchess of Devonshire, after the death of his father including offers of funds and accommodation (1756);

- Military recommendations for appointments for which the 4th Duke was responsible as Lord Lieutenant of Ireland; recommendations for estate livings and parliamentary seats on the Devonshire and Burlington estates; recommendations for royal household commissions under the responsibility of the 4th Duke as the Lord Chamberlain; other recommendations for appointments to Government;

- The political and personal friendships between the 4th Duke and Henry Fox; Thomas Pelham-Holles, 1st Duke of Newcastle; Henry Seymour-Conway; and Sir Robert Wilmot;

- The management and overseeing of the Irish estates of the Burlingtons via Mr Conner and Sir Anthony Abdy; and family affairs in Ireland relating to the Burlingtons, Boyles and Ponsonbys;

- The Seven Years War (1756-1763) including mention of: the catalyst for the beginning of war with France; the battle in Minorca and the eventual court-martialling of John Byng (CS4/522, CS4/523 and CS4/541); the Prussian Victory in Bohemia, October 1756; bad news from Bohemia and the King of Prussia s defeat, July 1757; Robert Clive and the East India Company in West Bengal (CS4/832); the convention signed by the Duke of Cumberland, September 1757; the failed expedition to Rochefort and the court of enquiry for Sir John Mordaunt in December 1757 (CS4/891, CS4/892); the embarkation at St Malo in June 1758 under Captain Howe (CS4/958, CS4/959); the capture of Lord Frederick Cavendish by the French at Montignon, September 1758 (CS4/1048, CS4/1053); the defeat of Montignon; the surrender of Guadeloupe (CS4/1138); the Battle of Minden, August 1759 (CS4/1148-1149); Prussian victory at Lunnerdorf, August 1759 (CS4/1161); the capture of Quebec, October 1759 (CS4/1176); the arrival of troops on Martinique 1761 (CS4/1334); failed peace negotiations with France, Summer 1761, with Duc de Choiseul, Bussy and Stanley; resolution to abandon the war in Germany in April 1762 (CS4/1627); renewed peace negotiations in May 1762 (CS4/1639); British and allied victory at Grebenstein, June 1762; the capture of Havana and 12 Spanish ships (September 1762);

- Reference to 18th-century cultural pursuits such as literature, balls and dancing, theatre, opera and architecture in correspondence with Garrick, George Canning, James Paine, William Mason, Horace Walpole, Joseph Spence and Elizabeth Chudleigh (e.g. CS4/1558);

- The political activities occurring in the British Parliament in London during the 4th Duke s secondment in Ireland (1755- May 1756);

- Financing of the war through a subscription for raising public supplies , with advice from the banker Sampson Gideon, 1757 (CS4/584, CS4/584, CS4/590, CS4/591);

- Irish Parliamentary politics relating to the 4th Duke s role as Lord Lieutenant of Ireland, 1756-Jan 1757; and political updates from the Irish parliament and struggles of the administration involving the Speaker and Primate, November 1757, via various political allies including John Bowes, later Lord Chancellor of Ireland and James Fitzgerald, 20th Earl of Kildare (1756-58);

- The plague outbreak in Algiers and quarantining ships into Ireland in 1756 (CS4/187);

- The Paddington Road Bill, April 1756 and the battle between the Dukes of Grafton and Bedford on the matter;

- The 4th Duke s preparations to return to England from Ireland (May 1756);

- Reference to a French cargo ship from Santo Domingo [Dominican Republic] in the Caribbean Islands captured at Waterford, Ireland (CS4/235, CS4/236);

- Intelligence reports for the British Government from Thomas Edward via his friend on the continent and Anthony Coghlan (Summer 1756 onwards) and through Précis of the Dutch Mail (1761-62);

- Local matters occurring in Derbyshire reported to the 4th Duke by the landowner Sir William Fitzherbert at Tissington such as the flour mill rioters in Derby, September 1756, (CS4/355) and Hall s ballad on pulling down mills (CS4/881, CS4/889);

- Local riots at Chatsworth and Bakewell against the Militia Act and the perception of enlistment into the foreign war , handled by Alexander Barker, agent at Chatsworth in August 1757 (CS4/809, CS4/810, CS4/811, CS4/818) and arming Chatsworth in 1760 (CS4/1217);

- The corn scarcity in Ireland, December 1756 (CS4/451, CS4/472, CS4/500);

- Multiple resignations from Government including: Newcastle and Fox in October 1756; the negotiations between the King and ministers surrounding appointing a new administration in 1757 and 1762 including the issue of certain individuals not being willing to work with other candidates (CS4/726);

- The Countess of Yarmouth s involvement in the negotiation of a new administration and the 4th Duke s appointment as First Lord of the Treasury (Summer 1757);

- Royal matters including holding court at Windsor (CS4/1685); funerals; closet meetings; commissions; the administration of the 4th Duke s role as Lord Chamberlain (1757-1762) through Sir Robert Wilmot; the King s jewellery (CS4/1372); the birth of Queen Charlotte s first child (CS4/1707); and the King s sentiments on political matters and foreign affairs;

- The case of soldiers tried for the death of George Headley in 1758 (CS4/915, CS4/991, CS4/999);

- The demise and death of Dorothy Boyle, Countess of Burlington and her will and estate, Summer 1758 (CS4/1050, CS4/1064);

- Reference to the Lord Chamberlain s unpopular power to prohibit performances of plays in response to Samuel Foot s plays The Author and The Minor (CS4/111, CS4/1116, CS4/1284);

- A description of the King meeting Kitty Fisher (CS4/1142);

- The case of murder by William Andrew Horne (CS4/1171);

- The dissolution of parliament after the King s death and letters to the Lord Chamberlain from post-holders requesting to keep commissions, Autumn 1760;

- Horace Walpole s description of his visit to Haddon and Hardwick in 1760 (CS4/1265);

- National politics and the election of MPs, including the Harwich seat concerning Mr Davy and Lord Coke s objections to him; the general election 1761 and Derbyshire seats;

- A description of unpleasant conditions in Senegal where troops were posted in 1761 (CS4/1373);

- Political wrangling between Newcastle, Bute and Pitt over the peace negotiations with reference to the Newfoundland fisheries, Summer 1761;

- The administration of the Royal Wedding and Coronation of King George III and Queen Charlotte, by the Lord Chamberlain, Summer 1761 (e.g. CS1/1495);

- Accounts of parliamentary debates concerning the continuation of the War in 1761, by Lord John Cavendish (e.g. CS4/1568);

- The Russian Palace Revolution involving the deposition of Peter III of Russia by Catherine, Empress of Russia, June 1762 (CS4/1707, CS4/1713);

- The declining mental and physical health of the 4th Duke and his recuperation at Bath, Summer 1762 (CS4/1758);

- The 4th Duke s absence from privy council meetings (CS4/1759);

- The death of Sampson Gideon in October 1762 and his will and estate (CS4/1791);

- The 4th Duke s own resignations in November and December 1762 as Lord Chamberlain and Lord Lieutenant of Derbyshire and the response from ministers and King George III to the 4th Duke s actions (CS4/1795, CS4/1773, CS4/1840, CS4/1802, CS4/1854);

- The case of Wilkes provoked by his publication of the North Briton in 1763 and arguments surrounding Parliamentary Privilege and Sir Charles Pratt s judgement as Lord Chief Justice, February 1764 (1898, CS4/1904, CS4/2002.1);

- Political manoeuvres and conversations between the Duke of Newcastle, William Pitt and other politicians to negotiate new commissions for political allies, following the prediction of the collapse of another Government Administration in Summer 1763.

Many of these letters provide evidence of the esteem in which the 4th Duke was held and his reputation as a diplomatic, fair and popular politician during a particularly turbulent decade of British politics (for example, CS4/473). These letters show he was kept informed of decisions and conversations even when they did not directly affect his own work, and demonstrate his colleagues use of him as a sounding board.

The letters shed light on the inner-workings of parliament and court through the Seven Years War and the opinions politicians at the time held of each other and the situation. It shows the chaotic nature of foreign affairs and home politics in the management of a war that is now considered integral to the British colonisation of large parts of Canada, South Asia and the Caribbean.

There is a lack of surviving letters in this collection between the 4th Duke and his children William nicknamed Cann (Lord Hartington), Dorothy, Richard and George. The letters between the 4th Duke and Lady Burlington (their grandmother) provide the most references to his children and show that they were living apart from their father at Chiswick at least until her death in 1758. There is also mention of the children living at Devonshire House and Lord Hartington going to school at Harrow (according to letters between Dr Newcome and the 4th Duke). The letters between Dr Newcome and the 4th Duke shed light on the 4th Duke s concern for Lord Hartington s education and his reserved nature (CS4/98, CS4/328, CS4/788, and CS4/2027). There is also a letter between Lady Rockingham and the 4th Duke where Lady Rockingham requests a visit from Lady Dorothy (CS4/1996).

The peripatetic nature of the 4th Duke's existence and his enjoyed past-times such as hunting and horseracing are also captured in these letters.

William Cavendish, 4th 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, 3rd Duke of Devonshire (1698–1755), politician and landowner, and his wife, Katherine (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, 3rd 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 a part 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 1st 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 1st 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. Under British rule, the Irish executive government based at Dublin Castle was led by the Lord Lieutenant, or Viceroy, the king's representative in Ireland. His immediate subordinate was the Chief Secretary, and directly below this post, a resident Under Secretary was responsible for the day to day running of the administration.

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 4th Duke of Devonshire. He returned to England in May 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 Devonshire–Pitt 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 Newcastle–Pitt 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."

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 perhaps showed his solidarity by refusing to attend cabinet. He also spent much of this summer in Bath for health reasons which may have been a contributing factor to his absence from council. This anomalous situation, whereby he retained his office yet absented himself from the business of government, could not be tolerated for long. When the King's ministers called him back to a meeting about the peace treaty and he refused on the grounds that he could not usefully contribute having been absent from so many meetings, he riled the king. Adding to this, 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. In solidarity with Lord Rockingham and Newcastle who had been dismissed from their posts as Lord Lieutenants, Devonshire resigned 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.

[Source: Schweizer, Karl Wolfgang. "Cavendish, William, fourth duke of Devonshire (bap. 1720, d. 1764), prime minister." Oxford Dictionary of National Biography. 23 Sep. 2004; Accessed 9 Mar. 2022. https://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-4949. By permission of Oxford University Press].

This collection is arranged in accordance with ISAD(G): General International Standard Archival Description, Second Edition, Ottawa 2000 and The Devonshire Collection Cataloguing Guidelines.

When this correspondence was extracted from CS1 between 1970 and 2000, it was rearranged into strict chronological order, with undated letters put at the end of each estimated year of creation. This arrangement included separating enclosed letters from their enclosures where the dates differed. In other words, often an enclosure comes in the sequence several letters before the letter that mentions it as an enclosure to the 4th Duke.

In the most recent cataloguing project to make this catalogue available online, the arrangement was left in its current calendar format, and detailed item-level descriptions of each letter were written with cross-reference to enclosures, where they are known, added to the "separated material" field.

The old reference numbers have been included in the new catalogue in the "former reference" field and are likely to be the references that appear in 20th century and earlier publications that reference this material.

The collection is open for consultation. Access to the archive at Chatsworth is by appointment only. For more information please visit: https://www.chatsworth.org/art-archives/access-the-collection/archives-and-library/.

All letters from Alexander Barker in this collection have transcriptions available from Chatsworth Archives.

A copy of the original typescript calendar catalogue written by Andrew Peppitt is available to consult.

There is a typescript index of writers and recipients of the letters for this collection also available for consultation.

This catalogue was produced with support from Archives Revealed, funded by The National Archives, The Pilgrim Trust and The Wolfson Foundation.

Copies of material in the archive can be supplied for private study and personal research purposes only, depending on the condition of the documents.

The 4th Duke's notes titled "Memoranda on the State of Affairs" (1759-1762) were stored with CS4, and referenced as CS1/260.247-372. This file has been removed and is now catalogued as DF2/5.

A number of items listed as part of the "Additional Series" at Chatsworth (GB 2495 AS) were identified as belonging with the 4th Duke's correspondence and moved from AS/3279 and re-catalogued as:

- CS4/136.1

- CS4/501.1

- CS4/1274.1

- CS4/2002.1

- CS4/2002.2

- CS4.2002.3.

It was not until the 1920s that an effort was made to comprehensively catalogue the family, social and political correspondence that had accumulated through the centuries at Chatsworth.

During 1925 and 1926, all letters of the Cavendish family and associates of the family dated before and including 1839 were catalogued as the First Correspondence Series (CS1). However, from the 1970s to the 2000s, the correspondence of the 4th, 5th and 6th Dukes of Devonshire, their families and associates were extracted to form, respectively, the 4th Duke's Group (CS4); the 5th Duke's Group (CS5) and the 6th Duke's Group (CS6).

This collection is the 4th Duke's Group and comprises all the correspondence of the 4th Duke from 6th December 1755 - the date he inherited the dukedom from his father - up to September 1764, a month before his death.

Most letters in this collection at Chatsworth Archives were sent directly to the 4th Duke wherever he was (Dublin, London, Londesborough, Newmarket, Bath, Chatsworth etc.) and then likely remained at or returned to Chatsworth with his other papers after his death.

There are some original letters written by the 4th Duke and delivered to recipients that have also been returned to Chatsworth. These are mostly from the 4th Duke to his brother Lord Frederick Cavendish and to Prince William, Duke of Cumberland. Some letters from Lord Frederick to Prince William are also included in this collection.

It is assumed that these letters returned to Chatsworth from the possession of Lord Frederick, possibly after his death in 1803. The letters from the 4th Duke to Prince William may also have returned to Chatsworth via Lord Frederick as he was Lord of the Bedchamber and aide-de-camp to Prince William during the Seven Years' War. In some cases, both the copy letter and the original written by the 4th Duke to Prince William or Lord Frederick now exist in this collection.

Many of the letters the 4th Duke received are endorsed on the back with the sender and the date, showing the 4th Duke's intention to keep letters for later reference.

The original letters that were sent to Lady Burlington which now exist in this collection were likely inherited and brought to Chatsworth (along with much of CS 1) by the 4th Duke after the death of Lady Burlington in 1758.

The following collections at Chatsworth hold very similar material relating to CS4, but are distinct collections with their own catalogues/ lists:

-Cavendish Family and Associates 1st Correspondence Series (GB2495 CS1) includes all correspondence of the 4th Duke up to December 1755 when he inherited the Dukedom;

-Papers of William Cavendish, 4th Duke of Devonshire 1740-1768 (GB 2495 DF2) are other memoranda, accounts and correspondence of the 4th Duke and includes his Memoranda on State of Affairs 1759-62;

- Burlington Miscellaneous Manuscripts (GB 2495 BU) includes papers of the 4th Duke's parents-in-law from whom he inherited the Burlington Estate - Dorothy Boyle (née Savile), Countess of Burlington and Richard Boyle, 3rd Earl of Burlington;

-Chatsworth Building accounts (GB 2495 CH37) feature the details of building work at Chatsworth;

-Records of the Chatsworth Estate Office 1704-1955 (GB 2495 DE/CH) includes records relating to the management of the 4th Duke's Chatsworth estate;

-The Currey Papers (GB 2495 L) include papers relating to the 4th Duke's inherited estates from the Boyle family in London, Yorkshire and Ireland and include some papers relating to political seats and positions associated with these estates;

See: Derbyshire Record Office (D3155 - Correspondence Series): "Wilmot-Horton family of Osmaston and Catton" for authors and recipients as well as topics that also appear in this collection.