Kingdom of Northumbria

The Kingdom of Northumbria (c. 604-954 CE) was a political entity in the north of modern-day Britain with Mercia directly to the south, the Kingdoms of the Welsh to the west, and the land of the Picts to the north; the eastern line of the kingdom was bordered by the sea. The region was originally divided between the two kingdoms of Bernicia (in the north) and Deira (south) but the people were referred to as Northumbrians, (meaning “those north of the Humber River”). These two kingdoms often fought against each other until they were united under the reign of Aethelfrith (r. 593-616 CE) but their rivalry would continually destabilize the region throughout its history.