Margaret Bentinck, Duchess of Portland

The Duchess of Portland
Margaret Cavendish Bentinck, Duchess of Portland by Christian Friedrich Zincke, 1738
Personal details
Born11 February 1715
Welbeck Abbey, Nottinghamshire
Died17 July 1785
Bulstrode Park, Buckinghamshire
NationalityBritish
SpouseWilliam Bentinck, 2nd Duke of Portland
ChildrenElizabeth Thynne, Marchioness of Bath
Henrietta Grey, Countess of Stamford
William Cavendish-Bentinck, 3rd Duke of Portland
Lady Margaret Bentinck
Lady Frances Bentinck
Lord Edward Bentinck
Parent(s)Edward Harley, 2nd Earl of Oxford and Mortimer
Lady Henrietta Holles
OccupationArt and natural history specimens collector

Margaret Cavendish Bentinck, Duchess of Portland (11 February 1715 – 17 July 1785) was the richest woman in Great Britain of her time, styled Lady Margaret Harley before 1734, Duchess of Portland from 1734 to her husband's death in 1761, and Dowager Duchess of Portland from 1761 until her own death in 1785.

The duchess, an heiress on a huge scale had the largest natural history collection in the country, complete with its own curator, the parson-naturalist John Lightfoot, and the Swedish botanist Daniel Solander. Her collection included costly art objects such as the Portland Vase. Her ambition for her collection was for it to contain and to describe every living species.

She was a member of the Blue Stockings Society, a group of social intellectuals led by women and founded by her great friend Elizabeth Montagu.