Mary Churchill (about 1689-1751) was the daughter of Sir John Churchill, first Duke of Marlborough, and Sarah Jennings, Duchess of Marlborough. In 1704 or 1705, she married John, Duke of Montague and Marquis d’Monthermer. Mary Churchill’s dress inventory of 1747 was published in a 1997 issue of Costume, the journal of the Costume Society in England.