William Cavendish, 3rd Earl of Devonshire

William Cavendish, 3rd Earl of Devonshire, KB, FRS (c. 10 October 161723 November 1684) was an English nobleman and politician, known as a royalist supporter.

Life The eldest son of William Cavendish, 2nd Earl of Devonshire and his wife Christian Cavendish, Countess of Devonshire, he was educated by his mother with his father's old tutor Thomas Hobbes. Hobbes's translation of Thucydides is dedicated to Cavendish, and from 1634 to 1637 he travelled abroad with the philosopher.

Cavendish was created a Knight of the Bath at Charles I's coronation in 1625. He was Lord Lieutenant of Derbyshire from 13 November 1638 to 22 March 1642, was high steward of Ampthill 4 February 1640, and joint-commissioner of array for Leicestershire 12 January 1642. As a prominent royalist he opposed Strafford's attainder, was summoned to a private conference with the queen in October 1641, was with Charles I at York in June 1642, absented himself from his place in the parliament, was impeached with eight other peers of high crimes and misdemeanors, refused to appear at the bar of the House of Lords, was expelled on 20 July 1642, and was ordered to stand committed to the Tower of London. He left England, and his estates were sequestrated. ), married Charles, Lord Rich, son of the Earl of Warwick; and then John Cecil, 5th Earl of Exeter on 2 May 1670 and had issue.