William was killed in a tournament at
Croydon in 1286,[1] predeceasing his father. It has been suggested that this was murder, planned in advance by William's enemies.[2][3] On the 6th Earl's death the title went to John, the only son of William.[4] John died without legitimate children, so on his death the title passed to
Richard FitzAlan, 10th Earl of Arundel, eldest son of Edmund FitzAlan and John's sister Alice.
^
abFrederick Lewis Weis, Walter Lee Sheppard and William Ryland Beall, The Magna Charta Sureties, 1215: The Barons Named in the Magna Charta, 1215, and Some of Their Descendants who Settled in America During the Early Colonial Years (Genealogical Pub. Co., 1999), p. 184
^Juliet R. V. Barker, The Tournament in England, 1100-1400 (Boydell Press, 1986), p. 47
^From William's Oxford Inquisition Post Mortem taken on the Friday after Epiphany, 15 Edw. I: "John his son, born at the feast of the Nativity of St. John the Baptist, 14 Edw. I, is his next heir. ""Inquisitions Post Mortem, Edward I, File 47: 633. William de Warrenna. Inq. (Oxford). Friday after Epiphany, 15 Edw. I". Sharp, J.E.E.S, ed. (1906). Calendar of Inquisitions Post Mortem: Volume 2, Edward I. London: His Majesty's Stationery Office. p.382. Accessed via Internet Archive. Retrieved 17 June 2021.