The Battle of Heavenfield took place in 634 AD near the village of Heavenfield in present-day England. It was a significant conflict between the forces of the Northumbrian king, Oswald, and the invading army of Cadwallon, the king of Gwynedd. This battle was crucial in establishing Northumbrian dominance in the region. King Oswald, supported by his allies, achieved a decisive victory at Heavenfield. The battle is notable for its role in the spread of Christianity in Northumbria, as Oswald was a devout Christian who sought to unify his kingdom under this faith. The victory also solidified Oswald's reign and influence in early medieval Britain.