Battle of Heavenfield

Date	634
Location	near Hexham (today part of Northumberland, England)
Result	Northumbrian victory

Belligerents

Northumbria

Gwynedd

Commanders and leaders

Oswald

Cadwallon ap Cadfan †

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 (Annals of Wales) 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.

Eanfrith, who had been exiled under Edwin, became king of Bernicia, whilst Deira was ruled by Osric, a cousin of Edwin. Eanfrith's reign was short, as he was killed by Cadwallon whilst trying to negotiate peace. According to Bede, Osric was killed by Cadwallon whilst trying to besiege him. Eanfrith's brother, Oswald, then returned from seventeen years exile in Dál Riata to claim the crown of Northumbria. However the threat of Cadwallon lingered and Oswald had to raise an army as soon as possible to deal with his invading force.

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