Einion ap Gollwyn
Einion ap Gollwyn (ap Collwyn, Eineon) (fl. 1093), was a Welsh prince and warrior supposed to have existed in the eleventh century. Not mentioned in medieval chronicles, he is the subject of possibly legendary or fictional writings from the sixteenth century onwards. Some Welsh family genealogies claimed descent from Einion.
Einion, the son of Collwyn, is mentioned only in the legendary accounts of the conquest of Glamorgan by the Normans. Cydifor (Cedivor) of Dyfed who may have been his brother is a historical figure, said to have died in 1092. Cedivor's son Llewelyn rose in revolt against Rhys ap Tewdwr, the chief king of South Wales, but was overthrown by him at Llandydoch. These troubles gave assisted the Anglo-Norman marcher lords who were extending their conquests in Wales. Next year Rhys was slain by the French of Brycheiniog. The conquests of Dyfed and Ceredigion immediately followed. This history is authentic, but Einion's name does not appear in records of it.
The legend now begins. Einion, the brother of Cedivor, fled from the triumph of Rhys at Llandydoch to Iestyn ap Gwrgan (son of Gwrgan) prince of Morganwg, who was also a rebel against Rhys. Now Einion had been previously in England, had served the king in France and other lands, and knew both William Rufus himself and his great barons well. He proposed to Iestyn to bring his Norman friends to the latter's help on condition of his receiving as his wife the daughter of Iestyn and as her portion the lordship of Miscin. Iestyn accepted the proposal. Einion visited his English friends at London. He persuaded Robert FitzHamon, historically lord of the honour of Gloucester, and twelve other knights, to bring a great army to the aid of Iestyn. Rhys was slain by them in a terrible battle near the boundaries of Brycheiniog, at Hirwaun Gwrgan. With Rhys fell the kingdom of South Wales.
The Normans, having done their work for Iestyn, received their pay and returned towards London. They had hardly departed when Iestyn, flushed with his triumph, treacherously refused Einion his daughter's hand. Einion pursued the retreating Frenchmen, explained to them his own wrongs and the general unpopularity of Iestyn, and showed how easy it would be for them to conquer Iestyn's dominions, since his treason to Rhys had so much disgusted the South Wales princes that not one would afford him succour. The Normans were easily persuaded. Einion meanwhile organised a Welsh revolt. They jointly spoiled Morganwg, but the Normans took the rich Vale of Glamorgan for their own share and left Einion only the mountainous areas of Senghenydd and Miscin, while the sons of Iestyn were rewarded for their acquiescence in their father's fate by the lowland lordship of Aberafan. Induced by the victory of FitzHamon, other Normans seized on Dyved, Ceredigion, Brycheiniog. Thus the treachery of Einion put all South Wales into the hands of the foreigner.
This full and elaborate story is first found in the "Brut y Tywysogion", first printed in the second volume of the Myvyrian Archaeology, and later with a translation by Aneurin Owen for the Cambrian Archæological Association in 1863. But the original manuscript of this "Brut" is believed not to be older than the middle of the sixteenth century, and therefore not much earlier than David Powel's History of Cambria (1584), in which the story of the conquest of Glamorgan also appears at length, varying from the above account in only a few details. There are here added, however, long pedigrees of the descendants of the Twelve Knights of Glamorgan, and it has been suggested that inventors of the pedigrees for Glamorganshire families created the legend.