Question: Who is the paternal grandfather of Gruffudd Ab Owain Glyndŵr?

Knowledge 1: Gruffudd ab Owain Glyndŵr
Gruffudd ap Owain Glyndŵr (c.1375-c.1412) was the eldest son of Margaret Hanmer and Owain Glyndŵrthe disinherited Prince of the old Royal house of Powys Fadog who led a major revolt in Wales between 1400 and c.1416. [SEP] Knowledge 2: Owain Glyndŵr
Owain ab Gruffydd, lord of Glyndyfrdwy (c. 1359 – c. 1415), or simply Owain Glyndŵr or Glyn Dŵr(anglicized to Owen Glendower), was a Welsh leader who instigated a fierce and long-running yet ultimately unsuccessful war of independence with the aim of ending English rule in Wales during the Late Middle Ages.He was the last native Welshman to hold the title Prince of Wales ("Tywysog Cymru").Glyndŵr was a descendant of the Princes of Powys through his father Gruffudd Fychan II, hereditary "Tywysog" of Powys Fadog and Lord of Glyndyfrdwy, and of those of Deheubarth through his mother ElenferchTomasap Llywelyn ab Owen.On 16 September 1400, Glyndŵr instigated the Welsh Revolt against the rule of Henry IV of England.The uprising was initially very successful and rapidly gained control of large areas of Wales, but it suffered from key weaknesses – particularly a lack of artillery, which made capturing defended fortresses difficult, and of ships, which made rebel-controlled coastlands vulnerable.The uprising was eventually suppressed by the superior resources of the English.Glyndŵr was driven from his last remaining strongholds in 1409, but he avoided capture; the last documented sighting of him was in 1412.He twice ignored offers of a pardon from his military nemesis, the new king Henry V of England, and despite the large rewards offered, Glyndŵr was never betrayed to the English.His death was recorded by a former follower in the year 1415.With his deathOwain acquired a mythical status along with Cadwaladr, Cynan and Arthur as a folk hero awaiting the call to return and liberate his people.In William Shakespeare's play "Henry IV, Part 1", the character of Owen Glendower is a wild and exotic king ruled by magic and emotion.In the late 19th century, the Cymru Fydd movement recreated him as the father of Welsh nationalism.
Knowledge 1: Owain Glyndŵr
Owain ab Gruffydd, lord of Glyndyfrdwy (c. 1359 – c. 1415), or simply Owain Glyndŵr or Glyn Dŵr(anglicized to Owen Glendower), was a Welsh leader who instigated a fierce and long-running yet ultimately unsuccessful war of independence with the aim of ending English rule in Wales during the Late Middle Ages.He was the last native Welshman to hold the title Prince of Wales ("Tywysog Cymru").Glyndŵr was a descendant of the Princes of Powys through his father Gruffudd Fychan II, hereditary "Tywysog" of Powys Fadog and Lord of Glyndyfrdwy, and of those of Deheubarth through his mother ElenferchTomasap Llywelyn ab Owen.On 16 September 1400, Glyndŵr instigated the Welsh Revolt against the rule of Henry IV of England.The uprising was initially very successful and rapidly gained control of large areas of Wales, but it suffered from key weaknesses – particularly a lack of artillery, which made capturing defended fortresses difficult, and of ships, which made rebel-controlled coastlands vulnerable.The uprising was eventually suppressed by the superior resources of the English.Glyndŵr was driven from his last remaining strongholds in 1409, but he avoided capture; the last documented sighting of him was in 1412.He twice ignored offers of a pardon from his military nemesis, the new king Henry V of England, and despite the large rewards offered, Glyndŵr was never betrayed to the English.His death was recorded by a former follower in the year 1415.With his deathOwain acquired a mythical status along with Cadwaladr, Cynan and Arthur as a folk hero awaiting the call to return and liberate his people.In William Shakespeare's play "Henry IV, Part 1", the character of Owen Glendower is a wild and exotic king ruled by magic and emotion.In the late 19th century, the Cymru Fydd movement recreated him as the father of Welsh nationalism. [SEP] Knowledge 2: Owen Tudor
Sir Owen Tudor (1400 – 2 February 1461) was a Welsh courtier and the second husband of Catherine of Valois (1401–1437), widow of King Henry V of England.He was the grandfather of Henry VII, founder of the Tudor dynasty.Owen was a descendant of a prominent family from Penmynydd on the Isle of Anglesey, which traces its lineage back to Ednyfed Fychan (d. 1246), a Welsh official and seneschal to the Kingdom of Gwynedd.Tudor's grandfather, Tudur ap Goronwy, married Margaret, daughter of Thomas ap Llywelyn ab Owain of Cardiganshire, the last male of the princely house of Deheubarth.Margaret's elder sister married Gruffudd Fychan of Glyndyfrdwy, whose son was Owain Glyndŵr.Owen's father, Maredudd ap Tudur, and his uncles were prominent in Owain Glyndŵr's revolt against English rule, the Glyndŵr Rising.
Knowledge 1: Owen Tudor
Sir Owen Tudor (1400 – 2 February 1461) was a Welsh courtier and the second husband of Catherine of Valois (1401–1437), widow of King Henry V of England.He was the grandfather of Henry VII, founder of the Tudor dynasty.Owen was a descendant of a prominent family from Penmynydd on the Isle of Anglesey, which traces its lineage back to Ednyfed Fychan (d. 1246), a Welsh official and seneschal to the Kingdom of Gwynedd.Tudor's grandfather, Tudur ap Goronwy, married Margaret, daughter of Thomas ap Llywelyn ab Owain of Cardiganshire, the last male of the princely house of Deheubarth.Margaret's elder sister married Gruffudd Fychan of Glyndyfrdwy, whose son was Owain Glyndŵr.Owen's father, Maredudd ap Tudur, and his uncles were prominent in Owain Glyndŵr's revolt against English rule, the Glyndŵr Rising. [SEP] Knowledge 2: Maredudd ab Owain Glyndŵr
Maredudd ab Owain Glyndŵr was a son of Margaret Hanmer and Owain Glyndŵr.He was the last significant active participant in the revolt raised by Glyndŵr in Wales between 1400 and c. 1416.

Answer: Gruffudd Fychan II