[4][8] Ednyfed is said to have first come to notice in battle, fighting against the army of Ranulph de Blondeville, 4th Earl of Chester who attacked Llywelyn,[5] this act of war was at the behest of King John of England.
[3][11] In 1215, he succeeded Gwyn ab Ednywain as Seneschal (Welsh: cynghellwr) of Gwynedd, roughly equivalent to Chief Councillor or Prime Minister.
[14] Ednyfed is recorded as having a dozen children and many more descendants, Professor Glyn Roberts of Dictionary of Welsh Biography noted, "Ednyfed's own descendants in the same period are found in the townships of Trecastell, Penmynydd, Erddreiniog, Clorach, Gwredog, Trysglwyn, and Tregarnedd in Anglesey, and in Crewyrion, Creuddyn, Gloddaeth, Dinorwig, and Cwmllannerch in Caernarfonshire.
They are also found in Llansadwrn in Carmarthenshire and at Llechwedd-llwyfan, Cellan, and Rhyd-onnen in Cardiganshire ... descendants formed a 'ministerial aristocracy' of considerable wealth, and their widespread possessions, combined with the favourable terms on which they were held".
Excavations on the site found to have Roman coins from the time of Constantine the Great, and was probably used by Monks as a lay by to rest and fish on route to Aberconwy Abbey near Maenan, in the Conwy Valley.
[13] In 1240 Ednyfed served as a witness to a charter that Dafydd ap Llywelyn wrote for Basingwerk Abbey, alongside his brothers Grono and Heilyn.
The Commission, using Matthew Paris' work, noted that Henry Tudor's royal ancestor was indeed Ednyfed Fychan.
On the wedding night, a 'pitiable beggar' arrived at the house and asked permission to borrow a harp with which to entertain the party with a song.