John de St John

Sir John St John (died 1302), of Basing in Hampshire, was an English landowner, soldier, administrator and diplomat who was a close confidant of King Edward I, serving him in many capacities. Origins Born in the 1230s, he was the son of Robert St John (died 1267) and his wife, believed to be Agnes Cantilupe, daughter of William Cantilupe (died 1251) and his wife Millicent Gournay. His paternal grandparents were William de Port (died 1239), who changed his last name to St John, and his wife Mabel. Career On the death of his father in 1267, he inherited extensive lands in Berkshire, Hampshire, where he was constable of Porchester Castle, Herefordshire, Kent, Sussex, were he held the significant lordship of Halnaker, and Warwickshire. Having been loyal to King Henry III throughout the civil wars, in 1269 he and his household were granted a pardon for any offences during the disturbances. After the king's death in 1272, he was a member of the council that sent the news to the successor King Edward I, then on crusade in Palestine. In 1276 he was one of the magnates present at the council at which judgment was given against Llywelyn ap Gruffudd, and he participated in Edward's invasions of Wales in 1277 and 1282. In 1283 he attended the assembly at Shrewsbury which tried Dafydd ap Gruffydd.