Devonshire, Duke of (1720-1764), William Cavendish, served as prime minister of Great Britain (now also called the United Kingdom) from November 1756 to May 1757. He was reluctant to accept the position. He agreed only after King George II promised that he could resign at the end of that session of Parliament. Devonshire took office after the resignation of the Duke of Newcastle, who resumed the premiership upon Devonshire’s resignation.
Devonshire was born William Cavendish in 1720. The Cavendishes were one of the most powerful political families in Britain. He was the oldest of seven children born to William Cavendish, 3rd Duke of Devonshire. William entered Parliament as representative for Derbyshire in the House of Commons in 1741. He married Charlotte Elizabeth Boyle, Baroness Clifford, in 1748. The couple had three sons and one daughter. Cavendish became the fourth Duke of Devonshire on the death of his father in 1755. In the same year, he became Lord Lieutenant of Ireland, holding that office until November 1756. Devonshire served as Lord Chamberlain (leading officer of the royal household) from 1757 until 1762. He died on Oct. 2, 1764, in Spa, Austrian Netherlands (now Belgium).