Originally it comprised two independent kingdoms, Bernicia and Deira.
At his death in 633 the kingdom was again divided, Deira falling to his nephew Osric, while Bernicia was occupied by Eanfrith son of ZEthelfrith.
After Oswald's defeat and death at the hands of Penda in 642 Bernicia fell to his brother Oswio, while Oswine son of Osric became king in Deira, though probably subject to Oswio.
OSWIO (c. 612-670), king of Northumbria, son of .Ã†thelfrith and brother of Oswald, whom he succeeded in Bernicia in 642 after the battle of Maserfeld, was the seventh of the great English kings enumerated by Bede.
BERNICIA, the northern of the two English kingdoms which were eventually united in the kingdom of Northumbria.