In 625 Cadwallon ap Cadfan King Gwynedd was appointed King Gwynedd.
Anglo-Saxon Chronicle. 633. This year King Edwin (age 47) was slain by Cadwalla and Penda, on Hatfield moor, on the fourteenth of October [Note. Some sources say 12 Oct 633]. He reigned seventeen years. His son Osfrid was also slain with him. After this Cadwalla and Penda went and ravaged all the land of the Northumbrians; which when Paulinus saw, he took Ethelburga (age 28), the relict of Edwin, and went by ship to Kent. Eadbald and Honorius received him very honourably, and gave him the bishopric of Rochester, where he continued to his death.
Bede. 634. But soon after, the king of the Britons, Caedwalla285, the unrighteous instrument of rightful vengeance, slew them both. First, in the following summer, he put Osric to death; for, being rashly besieged by him in the municipal town [Map]286, he sallied out on a sudden with all his forces, took him by surprise, and destroyed him and all his army. Then, when he had occupied the provinces of the Northumbrians for a whole year287, not ruling them like a victorious king, but ravaging them like a furious tyrant, he at length put an end to Eanfrid (age 44), in like manner, when he unadvisedly came to him with only twelve chosen soldiers, to sue for peace. To this day, that year is looked upon as ill-omened, and hateful to all good men; as well on account of the apostacy of the English kings, who had renounced the mysteries of the faith, as of the outrageous tyranny of the British king. Hence it has been generally agreed, in reckoning the dates of the kings, to abolish the memory of those faithless monarchs, and to assign that year to the reign of the following king, Oswald (age 30), a man beloved of God. This king, after the death of his brother Eanfrid (age 44)288, advanced with an army, small, indeed, in number, but strengthened with the faith of Christ; and the impious commander of the Britons, in spite of his vast forces, which he boasted nothing could withstand, was slain at a place called in the English tongue Denisesburna, that is, the brook of Denis289.
Note 285. Cf. II, 20, ad init.
Note 286. "In oppido municipio." Commentators are agreed that Bede means York. It was a Roman "Colonia," and is called a "municipium" by Aurelius Victor, though whether Bede attaches any definitely Roman meaning to the term seems doubtful. Ducange explains "municipium" as "castrum," "castellum muris cinctum."
Note 287. From the death of Edwin (October 12th, 633), for Oswald's (age 30) reign is reckoned as lasting nine years, including the "hateful year," and he was killed August 5th, 642. Cf. infra c. 9.
Note 288. i.e., probably before the end of 634.
Note 289. Not identified with any certainty, but probably the Rowley Water or a tributary of it. It cannot be, as has been suggested, the Devil's Water, which is clearly distinguished from it in a charter of the thirteenth century. Caedwalla must have fled southwards for eight or nine miles after the battle (cf. next note).
In 634 King Oswald of Northumberland (age 30) won a decisive victory over the army of the Cadwallon ap Cadfan King Gwynedd at the Battle of Heavenfield which was fought at Heavenfield [Map] around six miles north of Hexham [Map].
Cadwallon ap Cadfan King Gwynedd was killed at a place Bede describes as Denisesburna which is possibly Rowley Water some eight miles south of the site of the battle.