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Lady Joan Fitzalan, Countess of Hereford, Essex, and Northampton (1347/1348- 7 April 1419), was the wife of Humphrey de Bohun, 7th Earl of Hereford, 6th Earl of Essex, and 2nd Earl of Northampton. Joan was the mother of Mary de Bohun, the first wife of Henry of Bolingbroke who later reigned as King Henry IV of England, and Eleanor de Bohun, Duchess of Gloucester. She was the maternal grandmother of King Henry V of England.