Sir William de la Pole (1478 - sometime between October and November 1539), was an English lord, and Knight of Wingfield Castle in Wingfield, Suffolk. He was the son of John de la Pole, 2nd Duke of Suffolk (1442 - 1492) and Elizabeth Plantagenet (Elizabeth of York, Duchess of Suffolk) (1444 - 1504). He was held prisoner in Tower of London for 37 years till his death, longer than anyone else in history, for allegedly plotting against King Henry VII with his brothers Edmund and Richard, who fled the country in 1501, apparently after their conspiracy was detected.