Styled Marquess of Granby from 1711, he succeeded to the title in 1721, cutting short a brief career in the House of Commons, where he had represented Rutland as a Whig.

[1] He was one of the directors of the Royal Academy of Music, establishing a London opera company which commissioned numerous works from Handel, Bononcini and others.

He supported the creation of London's Foundling Hospital and was one of its founding governors when it received its royal charter in 1739.

For example, he did not buy on par with his grandson, Charles, the 4th Duke of Rutland, friend and patron of Sir Joshua Reynolds.

Nevertheless, he was a serious collector whose eye and temperament led him to buy smaller works of all the major European painters including Raphael, Titian, Bassano, Veronese, Guido Reni, and the Italianate northerners, especially Claude and the two Poussins.