Kingdom of Deira

Deira was the Yorkshire kingdom of post-Roman Britain, the Anglian realm between Humber and Tees from 450 to its merger into Northumbria. First Deywr of the Brythonic Parisi from the oak-derwent name, centred on great Petuaria, refortified, then Derventio-Malton and famed ancient Eboracum the boar-place, also called Ebrauc, of the Hen Ogledd, Coel Hen's old north, walled by Elmet and Bernicia, east to the North Sea, it turned Anglian when Derwent valley warriors came in the mid-fifth century and made Eoforwic, York, their capital, to the Vale of York. Aella stands first certain king in the late sixth century; Aethelfrith of Bernicia seized Deira in 604, but Aella's son Edwin took both Deira and Bernicia in 616 and ruled the north till 633. Oswine paid with his life in 651, Aethelwald held the remnant, and Bede still wrote of Deira in 731, long after the kingdom had melted into Northumbria.