Devonshire, William Cavendish, 4th duke of (1720-64). Cavendish came from a highly political Whig family. He entered Parliament at the age of 21 for Derbyshire, and succeeded as duke in 1755. After serving as master of the horse 1751-5, he was made lord-lieutenant of Ireland. In the crisis of 1756, conciliatory and trusted, he became 1st lord of the Treasury with Pitt as the driving force. When Pitt was obliged to come to terms with Newcastle, Devonshire was moved to be lord chamberlain 1757-62. In the new reign he and his Whig colleagues resented the ascendancy of Bute. After Newcastle resigned, Devonshire refused to attend councils and in November 1762 was dismissed by George III and his name removed from the Privy Council. Devonshire's early death robbed the Whigs of a future leader.

A Dictionary of British History. Copyright © 2001, 2004 by Oxford University Press. All rights reserved.