William Cavendish, 4th Duke of Devonshire

The Duke of Devonshire
Portrait by Thomas Hudson, c. 1750s
Prime Minister of Great Britain
In office
16 November 1756 – 29 June 1757
MonarchGeorge II
Preceded byThe Duke of Newcastle
Succeeded byThe Duke of Newcastle
Personal details
Born(1720-05-08)8 May 1720
Died2 October 1764(1764-10-02) (aged 44)
Resting placeDerby Cathedral
PartyWhig
Spouse
(m. 1748; died 1754)
ChildrenWilliam Cavendish, 5th Duke of Devonshire
Dorothy Bentinck, Duchess of Portland
Lord Richard Cavendish
George Cavendish, 1st Earl of Burlington
Parent(s)William Cavendish, 3rd Duke of Devonshire
Catherine Hoskins
Signature
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William Cavendish, 4th Duke of Devonshire (8 May 1720 – 2 October 1764), styled Lord Cavendish before 1729, and Marquess of Hartington between 1729 and 1755, was a British Whig statesman and nobleman who was briefly nominal Prime Minister of Great Britain. He was the first son of William Cavendish, 3rd Duke of Devonshire and his wife, Catherine (née Hoskins). He is also a great-great-great-great-great-grandfather of King Charles III through the king's maternal great-grandmother, Cecilia Bowes-Lyon, Countess of Strathmore and Kinghorne.

In October 1762, George III suspected that Devonshire and Thomas Pelham-Holles, 1st Duke of Newcastle, were plotting against him. He had mistaken a visit by Devonshire as a tender of resignation, but George refused to see him in person. Four days later, George personally struck out Devonshire's name from the list of Privy Councillors.

Cavendish's health declined during the 1760s. He visited the town of Spa in the Austrian Netherlands for treatment in its mineral baths, but he died there in October 1764. Dying at the age of 44 years and 147 days, Devonshire remains the shortest-lived British prime minister. Devonshire was buried at Derby Cathedral.