History of Northumberland - Anglian Kingdoms of Deira, Bernicia and Northumbria

Anglian Kingdoms of Deira, Bernicia and Northumbria

Conquests by Anglian invaders led to the establishment of the kingdoms of Deira and Bernicia. The first Anglian settlement was effected in 547 by Ida, who, accompanied by his six sons, pushed through the narrow strip of territory between the Cheviots and the sea, and set up a fortress at Bamburgh, which became the royal seat of the Bernician kings. About the end of the 6th century Bernicia was first united with the rival kingdom of Deira under the rule of Æthelfrith of Northumbria, and the district between the Humber and the Forth became known as the kingdom of Northumbria.

After Æthelfrith was killed in battle around 616, Edwin of Deira became king of Northumbria. Æthelfrith's son Oswald fled northwest to the Gaelic kingdom of Dál Riata where he was converted to Christianity by the monks of Iona. Meanwhile, Paulinus, the first bishop of York, converted King Edwin to Roman Christianity and began an extensive program of conversion and baptism. By his time the kingdom must have reached the west coast, as Edwin is said to have conquered the islands of Anglesea and Man. Under Edwin the Northumbrian kingdom became the chief power in Britain. However, when Cadwallon ap Cadfan defeated Edwin at Hatfield Chase in 633, Northumbria was divided into the former kingdoms of Bernicia and Deira and Christianity suffered a temporary decline.

In 634, Oswald defeated Cadwallon ap Cadfan at the Battle of Heavenfield, resulting in the re-unification of Northumbria. Oswald re-established Christianity in the kingdom and assigned a bishopric at Hexham, where Wilfrid erected a famous early English church. Reunification was followed by a period of Northumbrian expansion into Pictish territory and growing dominance over the Celtic kingdoms of Dál Riata and Strathclyde to the west. Northumbrian encroachments were abruptly curtailed in 685, when Ecgfrith suffered complete defeat by a Pictish force at the Battle of Nechtansmere.