William Cavendish-Bentinck, 3rd Duke of Portland

William Henry Cavendish Cavendish-Bentinck, 3rd Duke of Portland, KG, PC, FRS (14 April 1738  30 October 1809) was a British Whig and then a Tory politician during the late Georgian era. He served as Chancellor of the University of Oxford (1792–1809) and twice as the Prime Minister of Great Britain (1783) and then of the United Kingdom (1807–1809). The 24 years between his two terms as Prime Minister is the longest gap between terms of office of any British Prime Minister.

The Duke of Portland

Portrait by Matthew Pratt
Prime Minister of the United Kingdom
In office
31 March 1807  4 October 1809
MonarchGeorge III
Preceded byThe Lord Grenville
Succeeded bySpencer Perceval
In office
2 April 1783  18 December 1783
Preceded byThe Earl of Shelburne
Succeeded byWilliam Pitt the Younger
Lord President of the Council
In office
30 July 1801  14 January 1805
Prime MinisterHenry Addington
William Pitt the Younger
Preceded byThe Earl of Chatham
Succeeded byViscount Sidmouth
Home Secretary
In office
11 July 1794  30 July 1801
Prime MinisterWilliam Pitt the Younger
Preceded byHenry Dundas
Succeeded byLord Pelham
Personal details
Born(1738-04-14)14 April 1738
Nottinghamshire, England
Died30 October 1809(1809-10-30) (aged 71)
Burlington House, Westminster, England
Resting placeSt Marylebone Parish Church
Political party
(m. 1766; died 1794)
Children6, including William, 4th Duke; Lord William and Lord Charles
Alma materChrist Church, Oxford

Portland was known before 1762 by the courtesy title Marquess of Titchfield. He held a title of every degree of British nobility: duke, marquess, earl, viscount and baron. He is also a great-great-great-grandfather of Queen Elizabeth II through her maternal grandmother, Cecilia Bowes-Lyon, Countess of Strathmore and Kinghorne.

He was the leader of the Portland Whigs faction, which broke with the Whig leadership of Charles James Fox and joined with William Pitt the Younger in the wake of the French Revolution.