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The Kingdom of Deira (Yorkshire)

Expansion, Christianity, War with Mercia and The Birth of Northumbria


Kingdom of Deira & periodic domimions




A-Bernicia 616-633; B-North Rheged 616-633; C- Ynis Manau 616-633; D-South Rheged since 620; E-Ynis Môn 626-633; F-Lindisware since 626.


King Edwin led Deira to many victories in battle, his conquests expanding his dominions to include all but one of Yorkshire’s neighbouring kingdoms, Mercia.  Feeling both threatened by and jealous of Edwin’s success, the Mercian King, Penda, formed an alliance with King Cadwallon of Gwynedd ready to do battle with Deira. 

On 12th October 633, the alliance killed Edwin at the battle of Hatfield Chase. Edwin had two sons, one was killed in battle with him whereas the other was taken by his mother to France in fear for his life due to the rampaging armies of Penda and Cadwallon,  An heir to the Deiran throne was found in Edwin’s cousin, Osric.

Edwin had converted from paganism when he was baptised by Bishop Paulinus on Easter Day 627.  In doing so he became the first Christian, Angle king.  He commissioned the building of a church that was eventually to become York Minster and after his death in battle, he was venerated ‘Saint Ēadwine’ (St Edwin).

Interpretation of Edwin’s standard used here to represent the Kingdom of Deira.

Said by the Venerable Bede to be in the form of a Roman standard, this would likely be based on the purple and gold standard of Constantine, who was crowned Emperor at York three centuries earlier, but modernized with the influence of Bishop Paulinus who baptized and converted Edwin to Christianity.  The latin cross replaces Constantine’s labarum on the staff whilst on the vexillum (banner) three gold stripes representing the Holy Trinity replace Constantine’s three gold circles representing the Emperor’s family.


Kings of Yorkshire in the Kingdom of Deira era





626 to 633


King of Deira since 616 but Deira not comprising all Ceremonial Yorkshire until 626 after a programme of annexation. Killed in battle by Penda of Mercia and Cadwallon of Gwynedd.  Venerated ‘Saint Edwin’.

633 to 634


Cousin of Ēadwine.  Killed by Cadwallon of Gwynedd.

634 to 642     


Nephew of Ēadwine.  Also King of Bernicia.  Killed by King Penda of Mercia and venerated as Saint Oswald.

642 to 644


Brother of Oswald.  Also King of Bernicia.  Denounced by Deira.

644 to 651


Son of Osric.  Oswiu continued as king of Bernicia after people of Deira proclaimed Oswine’s accession.  Assassinated by Oswiu after refusing to battle against him.

651 to 654


Son of Oswald.  Withdrew from battle against his uncle Oswiu and beleived to have become a hermit in Kirkdale.

654 to 656


Second reign.  Deira and Bernicia merged as sub kingdoms of Northumbria in 656 from when Oswiu continued as Overlord.

656 to 664


Sub king under his father, Oswiu of Northumbria.  Seems to have abdicated to go on pilgramage to Rome.

664 to 670


Son and sub king to Oswiu of Northumbria.  Succeeded to throne of Northumbria on death of Oswiu in 670.

670 to 679


Son of Oswiu.  Sub king under Ecgfrith of Northumbria.  Killed in battle against Mercia.

The source of the Deiran royal family can be traced back to one man, Yffi, father of King Ælla and Ælfric. Although Ælfric was never a king his blood-line produced King Osric (son) and King Oswine (grandson) where it ended.  King Ælla’s blood-line produced Kings Æthelric and Edwin (sons) and through his daughter Acha, Kings Oswald and Oswiu (grandsons) and Kings Æthelwold, Alchfrith, Ecgfrith and Ælfwine (great grandsons).

The marriage of Princess Acha of Deira to Æthelfrith of Bernicia united the two royal families and in 656 the two kingdoms merged as Northumbria.  Deira continued as a sub-kingdom until the death of Ælfwine in 679, from which time Deira and Bernicia became provinces of the Kingdom of Northumbria.