Case unresolved? Gwenllian and the battle of Cedweli

The battle of Cedweli in 1136 is the first conflict that appears in no contemporary Welsh source. The single account for the battle appears in the writings of Gerald of Wales (1146-1223), who was not even born at the time. His account reads:

'In these parts [of Cedweli], after King Henry the first had been removed from human affairs, whilst Gruffudd ap Rhys, then prince of South Wales, had gone to North Wales to gather help, his wife Gwendolen, like an Amazonian queen and a second Penthesilea, led an army into these parts; but by Maurice London, then the lord of this place, and that excellent man, Geoffrey the bishop's constable, warlikely prepared for battle, killed in that place her son Morgan, and captured another called Maelgwn, which boys she had arrogantly brought with her in expedition, with many others she herself was finally run through by a sword and decapitated'.

- Giraldus Cambrensis, Opera VI, pp78-79

What to make of this? Firstly, Gerald was writing of his own relatives: Gruffudd ap Rhys was his grand-uncle. While Gruffudd was away, his wife 'Gwendolen' or Gwenllian apparently led an army into the commote of Cedweli, where she was met and defeated by the Normans. She and her two sons were killed.

One might argue that Gerald would have known the history of his own family. However, it seems odd the battle is not mentioned in any of the existing Welsh chronicles. Even stranger, the demise of a Welsh queen and her sons are nowhere else described. A major defeat, resulting in the loss of three members of the royal house of Deheubarth, ought to have at least rated a mention in the Bruts or Annales Cambriae.

We do at least know that Gwenllian existed. She is briefly mentioned in the Life of her father, Gruffydd ap Cynan:

'Ae verchet oed Guenlliant, a maryet, a rainillt, a sussana ac annest'

[His daughters were Gwenllian, and Margaret, and Rhainillt, and Susanna and Annest]

The site of the battle is currently remembered in the field named Maes Gwenllian, less than two miles north-east of Kidwelly castle. This may be a relatively modern designation, intended to lend weight to Gerald's story. Nearby there is a 'battle cairn' or crescent-shaped earthwork, traditionally said to mark the burial place of Gwenllian and her sons. Again, when and how this tradition arose is unknown.

In summary, was there a battle or no? Without further evidence either way, it can only be: case unresolved.