Bamburgh Northumberland United Kingdom

Some of the Angles of what will come to be called Bernicia may have been employed as mercenaries along Hadrian's Wall during the late Roman period.

Others are thought to have migrated north (by sea) from Deira in the early sixth century.

The first Anglian king in the historical record is Ida, who is said to have obtained the throne and the kingdom about 547.

His sons will spend many years fighting a united force from the surrounding Brythonic kingdoms until their alliance collapses into civil war.

Æthelric, one of the sons born to Ida of Bernicia, founder of the Anglian kingdom, becomes in 568 Bernicia’s fourth (known) king.

Theodric, another son of Ida and the fifth known ruler of the Anglo-Saxon kingdom of Bernicia, in 572 assumes the kingship.

Little is known of Theodric's life and reign, although Urien, the king of Rheged, is said to have subjected Theodric and his sons to a three day siege on the island of Lindisfarne.

According to medieval Welsh poetry (such as the poem Gweith Argoed Llwyfain [The Battle of Argoed Llwyfain or Battle of Leeming Lane] from the Book of Taliesin), Theodric is killed in battle by Urien's son, Owain mab Urien, after Theodric demands hostages and Owain refuses to give in.

Theodric is succeeded by his brother Frithuwald. (The earliest authorities differ widely on the order and the regnal years of the kings between the death of Ida in 592/593 and the beginning of Æthelfrith's rule.)

Æthelfrith, king of Bernicia, gains control of Deira around 604; the circumstances of this are unknown.

That he gained Deira through conquest is suggested by the exile of Edwin, son of the former king Ælla, and Hereric, Edwin's nephew, who are both notable members of the Deiran royal line; the short five-year reign of Aethelric of Deira, who ruled immediately prior to Æthelfrith's acquisition of Deira, may also indicate conquest.

D. P. Kirby on the other hand suggested that Æthelfrith's rule of both kingdoms may have represented "a formalization of an existing relationship" of cooperation between the two.

Kirby also pointed out that Edwin did not necessarily go into exile immediately, and considered it likely that Æthelfrith's hostility towards him "manifested itself only by degrees".

It is also around 604 that Æthelfrith's son Oswald is born.

Oswald's mother is Acha, daughter of Ælla, and thus Edwin's sister.

Although Bede does not explicitly say Æthelfrith married Acha, it is thought that he did so; he may have married her prior to taking power in Deira, in which case the marriage may have facilitated it, or he may have done so afterwards in order to consolidate his position there.

Northumbria falls into disarray after the slaying of Edwin, with Eanfrith returning from Pictland to take power in the subkingdom of Bernicia and …

King Cynegils of Wessex dies after a thirty-two-year reign and is succeeded by his son Cenwalh, who is still pagan, and who marries the sister of King Penda of Mercia.

Oswiu, King of Bernicia, head of the rival Northumbrian royal family, in 642 sends a priest named Utta to Kent, which is at this time 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 as King Penda of Mercia, the victor of Maserfield, dominates central Britain, Oswiu is 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.

Penda invades Bernicia and besiege Oswiu at Bamburgh.

Oswiu, now become overlord (bretwalda) over much of Great Britain, establishes himself as king of Mercia, setting up his son-in-law, Penda's son Peada, as a subject king over Middle Anglia.