Sir William de la Pole (died before 1319) was the fourth son of Gruffydd ap Gwenwynwyn and would have inherited the principality of Powys Wenwynwyn, if it had continued to descend in the male line according to Welsh law, instead of having been surrendered to Edward I and regranted to his father as a marcher lordship.
This descended (according to English law) to William's elder brother Owen de la Pole, and after the death of his son without issue to his daughter Hawise Gadarn, Lady of Powys, wife of John Charleton, 1st Baron Cherleton.
Contrary to a few reports, there is no evidence of any relationship to William de la Pole of Hull, merchant and financier to Edward III.
[1] Owen endowed his brothers with portions of his lordship (as his own feudal tenants), but all these reverted to Hawise, except what Sir William de la Pole had.
[2] Another daughter, Anchoretta de Burgh, married John Leighton of StreTton, later of Wattlesborough and Loton, Sheriff of Shropshire (d 1493).