Battle of Heavenfield

The Battle of Heavenfield was fought in 633 or 634 between a Northumbrian army under Oswald of Bernicia and a Welsh army under Cadwallon ap Cadfan of Gwynedd. The battle resulted in a decisive Northumbrian victory. The Annales Cambriae record the battle as Bellum Cantscaul in 631. Bede referred to it as the Battle of Deniseburna near Hefenfelth.
An alliance between Cadwallon of Gwynedd and King Penda of Mercia had led to an invasion of Northumbria. This was an odd alliance between a Christian king of Brythonic descent and a pagan king of Anglian descent. At the Battle of Hatfield Chase on 12 October 633, the invading Welsh and Mercians had killed Northumbrian king Edwin and Northumbria was split between its two sub-kingdoms, Bernicia and Deira. Cadwallon's army laid waste to Northumbria.

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