The Battle of Arfderydd (also known as Arderydd) was fought, 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...

, in 573. The opposing armies are variously given in a number of Old Welsh sources, perhaps suggesting a number of allied armies were involved. The main adversaries appear to have been Gwenddoleu ap Ceidio

Gwenddoleu ap Ceidio

Gwenddoleu ap Ceidio or Gwenddolau was a Brythonic king who ruled in Arfderydd . This is in what is now south-west Scotland and north-west England in the area around Hadrian's Wall and Carlisle during the sub-Roman period in Britain...

 and either the princely brothers, Peredur

Peredur

Peredur is the name of a number of men from the boundaries of history and legend in sub-Roman Britain. The most well known of them appear in the following literary and historical sources:-Gwrgi and Peredur, sons of Eliffer:...

 and Gwrgi, or King Riderch Hael

Riderch I of Alt Clut

Riderch I , commonly known as Riderch or Rhydderch Hael , was a ruler of Alt Clut and the greater region later known as Strathclyde, a Brittonic kingdom that existed on the valley of the River Clyde in Scotland during the British Sub-Roman period...

 of Strathclyde

Kingdom of Strathclyde

Strathclyde , originally Brythonic Ystrad Clud, was one of the early medieval kingdoms of the celtic people called the Britons in the Hen Ogledd, the Brythonic-speaking parts of what is now southern Scotland and northern England. The kingdom developed during the post-Roman period...

. Gwenddoleu was defeated, and his forces killed. His bard

Bard

In medieval Gaelic and British culture a bard was a professional poet, employed by a patron, such as a monarch or nobleman, to commemorate the patron's ancestors and to praise the patron's own activities.Originally a specific class of poet, contrasting with another class known as fili in Ireland...

, Myrddin Wyllt

Myrddin Wyllt

Myrddin Wyllt , Merlinus Caledonensis or Merlin Sylvestris is a figure in medieval Welsh legend, known as a prophet and a madman...

, went mad and ran into the forest. He is probably the original of the Arthurian character, Merlin. The Welsh Triads

Welsh Triads

The Welsh Triads are a group of related texts in medieval manuscripts which preserve fragments of Welsh folklore, mythology and traditional history in groups of three. The triad is a rhetorical form whereby objects are grouped together in threes, with a heading indicating the point of likeness...

 refer to this battle as one of the "Three Futile Battles of the Island of Britain", along with the Battle of Camlann

Battle of Camlann

The Battle of Camlann is best known as the final battle of King Arthur, where he either died in battle, or was fatally wounded fighting his enemy Mordred.-Historicity:...

 and the Battle of the Trees

Cad Goddeu

Cad Goddeu is a medieval Welsh poem preserved in the 14th-century manuscript known as the Book of Taliesin. The poem refers to a traditional story in which the legendary enchanter Gwydion animates the trees of the forest to fight as his army...

.

In a late 15th century manuscript, a story called 'Lailoken and Kentigern

Saint Mungo

Saint Mungo is the commonly used name for Saint Kentigern . He was the late 6th century apostle of the Brythonic Kingdom of Strathclyde in modern Scotland, and patron saint and founder of the city of Glasgow.-Name:In Wales and England, this saint is known by his birth and baptismal name Kentigern...

' places the battle on the plain between Liddel and Carwannok. This is believed to be at Arthuret

Arthuret

Arthuret is a civil parish in the Carlisle district of Cumbria, England. According to the 2001 census it had a population of 2,434. The parish includes the small town of Longtown and the village of Easton...

, near Longtown

Longtown, Cumbria

Longtown is a small town in northern Cumbria, England, with a population of around 3,000. It is in the parish of Arthuret and on the River Esk, not far from the Anglo-Scottish border. Nearby was the Battle of Arfderydd....

, in Cumberland

Cumberland

Cumberland is a historic county of North West England, on the border with Scotland, from the 12th century until 1974. It formed an administrative county from 1889 to 1974 and now forms part of Cumbria....

 (now Cumbria

Cumbria

Cumbria , is a non-metropolitan county in North West England. The county and Cumbria County Council, its local authority, came into existence in 1974 after the passage of the Local Government Act 1972. Cumbria's largest settlement and county town is Carlisle. It consists of six districts, and in...

).

In Welsh literature and mythology

The battle of Arfderydd is referenced numerous times in a number of medieval Welsh texts, including Trioedd Ynys Prydein

Welsh Triads

The Welsh Triads are a group of related texts in medieval manuscripts which preserve fragments of Welsh folklore, mythology and traditional history in groups of three. The triad is a rhetorical form whereby objects are grouped together in threes, with a heading indicating the point of likeness...

and the Red Book of Hergest

Red Book of Hergest

The Red Book of Hergest is a large vellum manuscript written shortly after 1382, which ranks as one of the most important medieval manuscripts written in the Welsh language. It preserves a collection of Welsh prose and poetry, notably the tales of the Mabinogion, Gogynfeirdd poetry...

. The Welsh Triads name Gwenddoleu's warband as one of the 'Three Faithful Warbands of the Island of Britain', going on to say that they "continued to battle for a fortnight and a month after their lord was slain." The retinue of Dreon the Brave "at the Dyke of Arfderydd" is named as one of the "Three Noble Retinues", while a listing of the three "Horse-Burdens" of Britain relates that Gwrgi, Peredur

Peredur

Peredur is the name of a number of men from the boundaries of history and legend in sub-Roman Britain. The most well known of them appear in the following literary and historical sources:-Gwrgi and Peredur, sons of Eliffer:...

, Dunawd the Stout

Dunod Fawr

Dunod Fawr is a figure known from the Welsh Genealogies believed to have been a noble in the post-Roman Hen Ogledd. Dunod was a son of Pabo Post Prydain and is believed to have succeeded his father as ruler of a small polity somewhere in what is now the North of England, possibly in Lonsdale and/or...

 and Cynfelyn Drwsgl were carried by a horse called Corvan, which enabled them to watch the clouds of dust ("battle-fog") coming from Gwenddolau and his (mounted) forces in the battle of Arfderydd.

The first song of the Black Book of Carmarthen

Black Book of Carmarthen

The Black Book of Carmarthen is thought to be the earliest surviving manuscript written entirely or substantially in Welsh. Written in around 1250, the book's name comes from its association with the Priory of St. John the Evangelist and Teulyddog at Carmarthen, and is referred to as black due to...

, The Dialogue of Myrddin

Myrddin Wyllt

Myrddin Wyllt , Merlinus Caledonensis or Merlin Sylvestris is a figure in medieval Welsh legend, known as a prophet and a madman...

 and Taliesin

Taliesin

Taliesin was an early British poet of the post-Roman period whose work has possibly survived in a Middle Welsh manuscript, the Book of Taliesin...

heavily references the battle, in which a number of warriors purported to have fought in the conflict are named: Cedfyl, Cadfan, Maelgwn, Erith, Gwrith, Bran, Melgan, Rhys, Cynelyn, Cyndur, the sons of Eliffer, and Dywel fab Erbin

Dywel fab Erbin

Dywel fab Erbin is a minor character and warrior of Welsh tradition, the son of Erbin and the brother of Geraint and Ermid. Alongside his brothers, he is named in the early Arthurian tale Culhwch ac Olwen as a knight of Arthur's court at Celliwig....

. A further poem Apple Trees states that Myrddin wore a "golden torque" at the battle before fleeing into the Caledonian Forest

Caledonian Forest

The Caledonian Forest is the name of a type of woodland that once covered vast areas of Scotland. Today, however, only 1% of the original forest survives, covering in 84 locations. The forests are home to a wide variety of wildlife, much of which is not found elsewhere in the British...

, while the poem The Dialogue of Gwyn ap Nudd and Gwyddno Garanhir states that Gwyn ap Nudd

Gwyn ap Nudd

Gwyn ap Nudd is a Welsh mythological figure, the king of the Tylwyth Teg or "fair folk" and ruler of the Welsh Otherworld, Annwn. Described as a great warrior with a "blackened face", Gwyn is intimately associated with the otherworld in medieval Welsh literature, and is associated with the...

, a mythological psychopomp

Psychopomp

Psychopomps are creatures, spirits, angels, or deities in many religions whose responsibility is to escort newly deceased souls to the afterlife. Their role is not to judge the deceased, but simply provide safe passage...

, was "at the place where was killed Gwendoleu, the son of Ceidaw, the pillar of songs, where the ravens screamed over blood."