Dame Margaret Helen Grenville, Hon Mrs Greville, DBE (1863–1942), was a British society hostess and philanthropist.
Born as Margaret Helen Anderson, she was the illegitimate daughter of William McEwan (1827-1913), a brewery multimillionaire, who later was elected as an M.P. (Member of Parliament).[1][2] Her mother, Helen Anderson (1835/1836 - 1906), was married to William Anderson, whose surname Margaret Greville used in her own youth.[3] William McEwan married Helen Anderson in 1885, following the death of William Anderson.[4] In 1891 Margaret Anderson married Hon. Ronald Henry Fulke Greville, eldest son of the 2nd Baron Greville. They had no children; he died in 1908.
She was a close friend of Queen Mary. She bequeathed all her jewels to Queen Elizabeth, The Queen Mother, including a diamond necklace reputedly belonging to Marie Antoinette, and a tiara and ruby necklace by Boucheron, all of which are currently in possession of the British Royal Family. She also left £20,000 to Princess Margaret, as well as £25,000 to Queen Victoria Eugenia of Spain.[5]
Greville was named a Dame Commander of the Order of the British Empire (DBE) in 1922. At her death, her estate "Polesden Lacey" in Great Bookham, Surrey, was bequeathed to the National Trust. She is buried on the grounds of Polesden Lacey.