Harry George Powlett, 4th Duke of Cleveland, styled The Honourable Harry Vane until 1827 and Lord Harry Vane from 1827 to 1864, who in 1864 adopted by Royal Licence the surname and arms of Powlett in lieu of Vane, was an English landowner, diplomat and Whig statesman. During the crisis which led to the collapse of Lord Russell's government in 1866 over the question of parliamentary reform, he was considered a possible compromise prime minister in a Whig-Conservative anti-reform coalition government, but such plans came to nothing.

William Henry Vane, 1st Duke of Cleveland, KG, styled Viscount Barnard until 1792 and known as The Earl of Darlington between 1792 and 1827 and as The Marquess of Cleveland between 1827 and 1833, was a British landowner, slave holder and politician.