Eanflæd (19 April 626 – after 685, also known as Enfleda) was a Deiran princess, queen of Northumbria After Oswiu's death in 670, she retired to Whitby Abbey, which had been founded by Hilda of Whitby. Eanflæd became the abbess around 680 and remained there until her death. The monastery had strong association with members of the Northumbrian royal family and played an important role in the establishment of Roman Christianity in England.
Birth, baptism, exile
Eanflæd's mother had grown up as a Christian, but her father was an Anglo-Saxon pagan and he remained uncommitted to the new religion when she was born on the evening before Easter in 626 at a royal residence by the River Derwent. Bede recounts that earlier on the day that Eanflæd was born, an assassin sent by Cwichelm of Wessex made an attempt on Edwin's life. Afterward, Edwin, prompted by Æthelburg's bishop, Paulinus, agreed to Eanflæd's baptism and promised to become a Christian if he was granted a victory over Cwichhelm. Eanflæd was baptised, Bede says, on the feast of Pentecost (8 June 626) with eleven others of the royal household.
Edwin campaigned successfully against Cwichelm and adopted the new faith in 627. His reign ended in 633 with his defeat and death at the battle of Hatfield Chase. Fleeing the unsettled times which followed Edwin's death, Æthelburg, together with Bishop Paulinus, returned to Kent, where Eanflæd grew up under the protection of her uncle, King Eadbald of Kent.
Return, marriage
In 642 Oswiu, King of Bernicia, head of the rival Northumbrian royal family,<!-- seems a better term than dynasty--> sent a priest named Utta to Kent, which then was ruled by Eanflæd's cousin, Eorcenberht, to ask for her hand in marriage. Oswiu already had been married, to a British princess, named Rieinmellt, but recently had become king on the death of his brother, Oswald, at the battle of Maserfield. King Penda of Mercia, the victor of Maserfield, dominated central Britain and Oswiu was in need of support. Marriage with Eanflæd would provide Kentish, and perhaps Frankish, support, and any children Oswiu and Eanflæd might have would have strong claims to all of Northumbria. The date of the marriage is not recorded.
Oswiu's marriage with Eanflæd was largely unsuccessful in ensuring the peaceful acceptance of his rule in Deira. By 644, Oswine, Eanflæd's paternal second cousin, was ruling in Deira. In 651 Oswine was killed by one of Oswiu's generals. To expiate the killing of his wife's kinsman, Oswiu founded Gilling Abbey at Gilling where prayers were said for both kings.
Children, patron of Wilfrid, supporter of Rome
With varying degrees of certainty, Eanflæd's children with Oswiu are identified as Ecgfrith, Ælfwine, Osthryth, and Ælfflæd. Oswiu's complicated series of marriages and liaisons makes identifying the mother of each of his children difficult. Kirby states that Aldfrith, Ealhfrith, and Ealhflæd were not born to Eanflæd.
Eanflæd was the early patroness of Wilfrid, who played a large part in Northumbrian politics during the reigns of Ecgfrith, Aldfrith, and Osred, and elsewhere in seventh century Britain. When Wilfrid wished to travel on pilgrimage to Rome, the Queen recommended him to her cousin, the Kentish king Eorcenberht.