Isabella de Forz, Countess of Devon (born 1237)

Isabel de Forz was the eldest daughter of Baldwin de Redvers, 6th Earl of Devon (1217–1245). On the death of her brother Baldwin de Redvers, 7th Earl of Devon, in 1262, without children, she inherited suo jure the earldom and also the feudal barony of Plympton in Devon, and the lordship of the Isle of Wight. After the early death of her husband and her brother, before she was thirty years old, she inherited their estates and became one of the richest women in England, living mainly in Carisbrooke Castle on the Isle of Wight, which she held from the king as tenant-in-chief.