Margaret Holles, Duchess of Newcastle upon Tyne

Margaret Cavendish (22 October 1661 – 24 December 1716, London) was the fourth of six children of Henry Cavendish, 2nd Duke of Newcastle-upon-Tyne and his wife Frances Pierrepoint.

On 1 March 1690 she married John Holles, 1st Duke of Newcastle-upon-Tyne (of the second creation in 1694, the first creation having become extinct in 1691 when her father died without a male heir -his son Henry Earl of Ogle having died in 1680). They had one child, Lady Henrietta Cavendish Holles (1694–1755), who married 2nd Earl of Oxford and Mortimer and was mother to Margaret Bentinck, Duchess of Portland.