William Cavendish, 5th Duke of Devonshire

His Grace
The Duke of Devonshire
KG
His Grace The Duke of Devonshire KG
	Portrait of the Duke of Devonshire painted in Rome by Pompeo Batoni, 1768
Lord High Treasurer of Ireland
	In office; 13 March 1766 – 1793
Monarch	George III
Preceded by	Vacant; William Cavendish, 4th Duke of Devonshire, 1764
Succeeded by	In Commission; Richard Boyle, 2nd Earl of Shannon, First Lord
Personal details
Born	14 December 1748
Died	29 July 1811 (aged 62)
Spouses	; Lady Georgiana Spencer (m. 1774; died 1806) ; Lady Elizabeth Hervey ; (m. 1809)
Children	Charlotte Williams (illegitimate); Georgiana Howard, Countess of Carlisle; Harriet Leveson-Gower, Countess Granville; William Cavendish, 6th Duke of Devonshire; Caroline St. Jules (illegitimate); Sir Augustus Clifford, 1st Baronet (illegitimate);
Parents	William Cavendish, 4th Duke of Devonshire; Charlotte Boyle, 6th Baroness Clifford;

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William Cavendish, 5th Duke of Devonshire, KG (14 December 1748 – 29 July 1811), was a British nobleman, aristocrat, and politician. He was the eldest son of William Cavendish, 4th Duke of Devonshire, by his wife, the heiress Lady Charlotte Boyle, suo jure Baroness Clifford, who brought in considerable money and estates to the Cavendish family. He was invited to join the Cabinet on three occasions, but declined each offer. He was Lord High Treasurer of Ireland and Governor of Cork, and Lord Lieutenant of Derbyshire. In 1782, he was made a Knight of the Order of the Garter.

The 5th Duke is most widely known for his marriage to his first wife Georgiana, Duchess of Devonshire. At the age of about twenty-one, Devonshire toured Italy with William Fitzherbert which is where they commissioned the pair of portraits by Pompeo Batoni.