William Cavendish, 2nd Duke Of Devonshire

William Cavendish, 2nd Duke of Devonshire (1672 – 4 June 1729), was a British nobleman and political figure. He was the eldest surviving son of William Cavendish, 1st Duke of Devonshire, and Lady Mary Butler. He held the title of duke from 1710 until his death and was involved in political affairs primarily as a member of the Whig party.

Born in 1672, Cavendish succeeded to the dukedom upon his father’s death. His early military involvement included probably commanding his father's troop of cavalry. In 1692, he participated as a volunteer in Flanders. His initial attempt to enter Parliament was through a by-election in 1691 for the House of Commons, which was unsuccessful. Subsequently, in 1695, he was elected to represent Derbyshire in the House of Commons, serving as a Member of Parliament (MP).

Cavendish was appointed to the Privy Council in 1707. He served as Lord President of the Council during two separate periods: from 1716 to 1718 and again from 1725 until 1729. His political career was associated with the Whig party and involved participation in government during the early 18th century.

In addition to his political activities, William Cavendish was a notable figure in the history of horse racing. He owned Flying Childers, a racehorse considered one of the first great thoroughbreds. The horse was sired by Darley Arabian, one of the foundational stallions in the development of the English thoroughbred. Cavendish initially intended to use Flying Childers as a hunter rather than for racing, but the horse eventually became a successful racer and prominent sire, although not a successful breeder himself. Flying Childers' lineage contributed to the breed's development, with his brother Bartlett's Childers becoming the male ancestor of the famed racehorse Eclipse.

William Cavendish married the Hon. Rachel Russell on 21 June 1688. Rachel was the daughter of William Russell, Lord Russell, and she served as a Lady of the Bedchamber at the court of Queen Anne. Together, they had ten children:

- Lady Mary Cavendish (18 August 1696 – 15 June 1719)

- William Cavendish, 3rd Duke of Devonshire (26 September 1698 – 5 December 1755)

- Lady Rachel Cavendish (4 October 1699 – 18 June 1780), married Sir William Morgan on 14 May 1723

- Lady Elizabeth Cavendish (27 September 1700 – 7 November 1747), married Sir Thomas Lowther, 2nd Baronet

- Lord James Cavendish (23 November 1701 – 14 December 1741)

- Lord Charles Cavendish (17 March 1704 – 28 April 1783), married Anne Grey on 9 January 1727, father of Henry Cavendish

- Lady Anne Cavendish (died 23 August 1780 aged 70)

- Lady Katherine Cavendish (died 12 September 1715 aged 9)

- Lord John Cavendish (died 11 May 1720 aged 12)

- Lady Diana Cavendish (died 12 February 1722)

William Cavendish died in 1729. His contributions spanned political service and interest in horse racing, with familial ties to prominent political and social figures of his time.