Oswald’s Wars (1633–641)
PRINCIPAL COMBATANTS: Oswald, king of Bernicia, and
Penda, king of Mercia vs. Cadwallon, king of Gwynedd,
Wales; later, Oswald vs. Penda
PRINCIPAL THEATER(S): England, primarily Northumbria
MAJOR ISSUES AND OBJECTIVES: Domination over Anglo-
OUTCOME: Oswald amassed a large Anglo-Saxon
kingdom, but was killed in battle by his former ally,
Penda, who elevated Mercia to a long period of
dominance over Anglo-Saxon England.
APPROXIMATE MAXIMUM NUMBER OF MEN UNDER ARMS:
TREATIES: No documents survive
During the Middle Ages, England was a region of fragmented
kingdoms. The death of Edwin (585–632), king of
Deira, enabled Oswald (c. 605–641), son of the Bernician
king Aethelfrith (fl. 593–616), to regain dominance of
both Bernicia and Deira after he had been exiled from
Northumbria (the region encompassing Bernicia and
Deira) in 616. With King Penda (c. 577–655) of Mercia,
Oswald now attacked King Cadwallon (d. 634) of
Gwynedd, in northern Wales. After a year of combat, the
forces of Cadwallon were defeated, and Cadwallon himself
killed at the Battle of Heavenfield in 634.
Oswald now fought to secure his Northumbrian borders
and extend his realms south. Along with battle, he
used a dynastic marriage to secure control of Wessex.
This, however, turned his ally Penda against him, and the
two led armies into combat at the Battle of Maserfeld in
641. There Oswald fell, propelling Penda and the kingdom
of Mercia to dominance over Anglo-Saxon England. Mercia
would come to dominate England for a century and a
half. Oswald, who had tried to bring peace to his realm
and who founded a famous monastery at Lindisfarne to
bring Christianity into pagan Northumbria, was later canonized.
See also AETHEBALD’SWARS (733–750); AETHELFRITH’S
Further reading: Frank Stenton, Anglo-Saxon England,
3rd ed. (Oxford, UK: Clarendon Press, 1971).