 His father Goronwy ab Ednyfed ( d.1268 ) was seneschal to Llywelyn ap Gruffudd ( also known as Llywelyn the Last ) , the King of Gwynedd by 1258 , continuing in the role until his death on 12 October 1268 . In that role , Goronwy had followed in the footsteps of his father , Ednyfed Fychan , and by doing so had tied the fortunes of the early House of Tudor to that of Llywelyn . Goronwy led Llywelyn 's military forces , such as in February 1263 when he took them as far south as Gwent in action against the Marcher Lords . Tudur ap Goronwy was one of three sons of Goronwy ab Ednyfed , alongside Goronwy ab Goronwy ( also known as Goronwy the Younger or Goronwy Fychan ) and Hywel ab Goronwy . Tudur Hen was not the first member of the family to be named Tudur . He was preceded by his uncle , Tudur ab Ednyfed , who had been in service to the previous Prince of Wales , Dafydd ap Llywelyn . 
