AC = "according to the Annales Cambriae

Annales Cambriae

Annales Cambriae, or The Annals of Wales, is the name given to a complex of Cambro-Latin chronicles deriving ultimately from a text compiled from diverse sources at St David's in Dyfed, Wales, not later than the 10th century...

".

The Battle of Hatfield Chase (O.E. Haethfelth) was fought on October 12, 633 at Hatfield Chase

Hatfield Chase

Hatfield Chase was a low-lying area in South Yorkshire, England which often flooded and is chiefly known from the Battle of Hatfield Chase in 633. It was a royal hunting ground until Charles I appointed the Dutch engineer Cornelius Vermuyden to drain it in 1626...

 near Doncaster

Doncaster

Doncaster is a town in South Yorkshire, England, and the principal settlement of the Metropolitan Borough of Doncaster. The town is about from Sheffield and is popularly referred to as "Donny"...

, Yorkshire

Yorkshire

Yorkshire is a historic county of northern England and the largest in the United Kingdom. Because of its great size in comparison to other English counties, functions have been increasingly undertaken over time by its subdivisions, which have also been subject to periodic reform...

, in Anglo-Saxon England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 between the Northumbria

Northumbria

Northumbria was a medieval kingdom of the Angles, in what is now Northern England and South-East Scotland, becoming subsequently an earldom in a united Anglo-Saxon kingdom of England. The name reflects the approximate southern limit to the kingdom's territory, the Humber Estuary.Northumbria was...

ns under Edwin

Edwin of Northumbria

Edwin , also known as Eadwine or Æduini, was the King of Deira and Bernicia – which later became known as Northumbria – from about 616 until his death. He converted to Christianity and was baptised in 627; after he fell at the Battle of Hatfield Chase, he was venerated as a saint.Edwin was the son...

 and an alliance of the Welsh

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

 of Gwynedd

Kingdom of Gwynedd

Gwynedd was one petty kingdom of several Welsh successor states which emerged in 5th-century post-Roman Britain in the Early Middle Ages, and later evolved into a principality during the High Middle Ages. It was based on the former Brythonic tribal lands of the Ordovices, Gangani, and the...

 under Cadwallon ap Cadfan

Cadwallon ap Cadfan

Cadwallon ap Cadfan was the King of Gwynedd from around 625 until his death in battle. The son and successor of Cadfan ap Iago, he is best remembered as the King of the Britons who invaded and conquered Northumbria, defeating and killing its king, Edwin, prior to his own death in battle against...

 and the Mercia

Mercia

Mercia was one of the kingdoms of the Anglo-Saxon Heptarchy. It was centred on the valley of the River Trent and its tributaries in the region now known as the English Midlands...

ns under Penda

Penda of Mercia

Penda was a 7th-century King of Mercia, the Anglo-Saxon kingdom in what is today the English Midlands. A pagan at a time when Christianity was taking hold in many of the Anglo-Saxon kingdoms, Penda took over the Severn Valley in 628 following the Battle of Cirencester before participating in the...

. The site was a marshy area about 8 miles NE of Doncaster on the south bank of the River Don. It was a decisive victory for the Welsh and Mercians: Edwin was killed and his army was defeated, leading to the temporary collapse of the Northumbrian state.

Background

Edwin, the most powerful ruler in Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 at the time, had apparently defeated Cadwallon a few years before the battle. Bede refers to Edwin establishing his rule over what he called the Mevanian islands, one of which was Anglesey

Anglesey

Anglesey , also known by its Welsh name Ynys Môn , is an island and, as Isle of Anglesey, a county off the north west coast of Wales...

, and another source refers to Cadwallon being besieged on the island of Priestholm

Puffin Island, Anglesey

Puffin Island is an uninhabited island off the eastern tip of Anglesey, Wales. It was formerly known as Priestholm in English and Ynys Lannog in Welsh.-Geography:...

 (AC: Glannauc), which is off the coast of Anglesey. Later, Cadwallon defeated and drove the Northumbrians from his territories and then allied with Penda (Cadwallon being the stronger member of the alliance). Penda's status in Mercia at this point is uncertain—Bede

Bede

Bede , also referred to as Saint Bede or the Venerable Bede , was a monk at the Northumbrian monastery of Saint Peter at Monkwearmouth, today part of Sunderland, England, and of its companion monastery, Saint Paul's, in modern Jarrow , both in the Kingdom of Northumbria...

 suggests he was not yet king, but became king soon after Hatfield; the Anglo-Saxon Chronicle, however, says that he became king in 626. The Welsh-Mercian army met Edwin in battle at Hatfield, north of Doncaster

Doncaster

Doncaster is a town in South Yorkshire, England, and the principal settlement of the Metropolitan Borough of Doncaster. The town is about from Sheffield and is popularly referred to as "Donny"...

.

Results of the battle

The battle was a disaster for Northumbria. With both Edwin and his son Osfrith killed, and his other son Eadfrith captured by Penda (and later killed), the kingdom was divided between its constituent kingdoms of Bernicia

Bernicia

Bernicia was an Anglo-Saxon kingdom established by Anglian settlers of the 6th century in what is now southeastern Scotland and North East England....

 and Deira. Eanfrith

Eanfrith of Bernicia

Eanfrith was briefly King of Bernicia from 633 to 634. He was the son of Æthelfrith, a Bernician king who had also ruled Deira to the south before being killed in battle around 616 against Raedwald of East Anglia, who had given refuge to Edwin, an exiled prince of Deira.Edwin became king of...

, a son of the former king Æthelfrith

Æthelfrith of Northumbria

Æthelfrith was King of Bernicia from c. 593 until c. 616; he was also, beginning c. 604, the first Bernician king to also rule Deira, to the south of Bernicia. Since Deira and Bernicia were the two basic components of what would later be defined as Northumbria, Æthelfrith can be considered, in...

, returned from exile to take power in Bernicia, while Edwin's cousin Osric

Osric of Deira

Osric was a King of Deira in northern England. He was a cousin of king Edwin of Northumbria, being the son of Edwin's uncle Aelfric...

 took over Deira. Cadwallon continued to wage a war of ruthless slaughter against the Northumbrians, and was not stopped until he was defeated by Oswald

Oswald of Northumbria

Oswald was King of Northumbria from 634 until his death, and is now venerated as a Christian saint.Oswald was the son of Æthelfrith of Bernicia and came to rule after spending a period in exile; after defeating the British ruler Cadwallon ap Cadfan, Oswald brought the two Northumbrian kingdoms of...

 at Heavenfield

Battle of Heavenfield

The Battle of Heavenfield was fought in 633 or 634 between a Northumbrian army under Oswald of Bernicia and a Welsh army under Cadwallon ap Cadfan of Gwynedd. The battle resulted in a decisive Northumbrian victory. The Annales Cambriae record the battle as Bellum Cantscaul in 631...

 (also known as Deniseburna, AC : Cantscaul) a year after Hatfield.

The historian D. P. Kirby suggested that the defeat of Edwin was the outcome of a wide-ranging alliance of interests opposed to him, including the deposed Bernician line of Æthelfrith; but considering the subsequent hostility between Cadwallon and Æthelfrith's sons, such an alliance must not have survived the battle for long.