Frances Julia Percy, Duchess of Northumberland (née Burrell; 21 December 1752 – 28 April 1820)[1] was the second wife of Hugh Percy, 2nd Duke of Northumberland, and the mother of the 3rd [2] and 4th Dukes.
Frances was a daughter of the barrister Peter Burrell, of Beckenham, Kent, and his wife, the former Elizabeth Lewis.[3] Her brother was Peter Burrell, 1st Baron Gwydyr, and two of her sisters also married into the aristocracy: Elizabeth, who married the Duke of Hamilton (and later the Marquess of Exeter), and Isabella, who became Countess of Beverley. Isabella's husband, Algernon, was the brother of Frances's husband, Hugh.