§ 1. a.d. 1039. In the first year of Gruffydd's reign over Gwynedd, his territories were invaded by the combined English and Danish forces of Mercia, acting in league with Howel ab Edwyn. Gruffydd, having encountered and defeated them at Croes yr Hafren, immediately led his triumphant army to Llanbadarn, where he destroyed the monastery, and drove away the monks because they had favoured his rival's cause. Passing from Powys into Deheubarth, he made a military progress through every district, receiving the submission of the subordinate rulers, while Howel ab Edwyn and his partisans fled for refuge to Earl Leofric's brother, Earl Edwin; and the fugitive prince prevailed on his ally to raise a powerful army for the purpose of replacing him upon the throne. When the Mercian force arrived at Pencadair, and was joined by Howel's old partisans, and the subjects of his district sovereignty, that prince believed his military strength to be invincible, and exulted in the sanguine anticipation of success; but Gruffydd ab Llewelyn, hearing of these proceedings, marched rapidly from Gwynedd at the head of his warriors, and came upon the allied host by surprise. In the battle which ensued, Earl Edwin, Earl Thurkell, Earl Elfget, and many other English noblemen, were slain, Howel effected his escape, but the victory of Gruffydd was complete, and even the wife of Howel fell into his hands.