The siege of Dumbarton was a successful four-month siege of the

Brittonic Brittonic or Brythonic may refer to: *Common Brittonic, or Brythonic, the Celtic language anciently spoken in Great Britain *Brittonic languages, a branch of the Celtic languages descended from Common Brittonic *Britons (Celtic people) The Br ...

fortress at

Dumbarton Rock Dumbarton (; also sco, Dumbairton; ) is a town in West Dunbartonshire, Scotland, on the north bank of the River Clyde where the River Leven flows into the Clyde estuary. In 2006, it had an estimated population of 19,990. Dumbarton was the ca ...

in 870, initiated by the

Viking Vikings ; non, víkingr is the modern name given to seafaring people originally from Scandinavia (present-day Denmark, Norway and Sweden), who from the late 8th to the late 11th centuries raided, pirated, traded and se ...

leaders

Amlaíb Olaf or Olav (, , or British ; Old Norse: ''Áleifr'', ''Ólafr'', ''Óleifr'', ''Anleifr'') is a Scandinavian and German given name. It is presumably of Proto-Norse origin, reconstructed as ''*Anu-laibaz'', from ''anu'' "ancestor, grand-father" a ...

King of Dublin Vikings invaded the territory around Dublin in the 9th century, establishing the Norse Kingdom of Dublin, the earliest and longest-lasting Norse kingdom in Ireland. Its territory corresponded to most of present-day County Dublin. The Norse refe ...

, and

Ímar Ímar ( non, Ívarr ; died c. 873), who may be synonymous with Ivar the Boneless, was a Viking leader in Ireland and Scotland in the mid-late ninth century who founded the Uí Ímair dynasty, and whose descendants would go on to dominate the Ir ...

. Dumbarton was capital of the Kingdom of Alt Clut, the only surviving Brittonic kingdom outside of

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

. It represented a valuable target for the Viking invaders, who were likely motivated by strategic considerations, as well as loot. The attackers may have wished to remove Alt Clut as a maritime power, and the location and defensiveness of Dumbarton itself was of major value. The siege lasted four-months, a length of time unprecedented in the history of Viking warfare in the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...

, and ended when the defenders ran out of water. After the siege numerous prisoners were taken and sold into slavery in Dublin. Following this defeat, the power centre of Alt Clut moved to the vicinity of

Govan Govan ( ; Cumbric?: ''Gwovan'?''; Scots: ''Gouan''; Scottish Gaelic: ''Baile a' Ghobhainn'') is a district, parish, and former burgh now part of south-west City of Glasgow, Scotland. It is situated west of Glasgow city centre, on the south ba ...

, and it became known as the

Kingdom of Strathclyde Strathclyde (lit. "Strath of the River Clyde", and Strað-Clota in Old English), was a Brittonic successor state of the Roman Empire and one of the early medieval kingdoms of the Britons, located in the region the Welsh tribes referred to as Yr ...

. The loss of Dumbarton caused the kingdom to increasingly fall under the influence of the Scottish

Kingdom of Alba The Kingdom of Alba ( la, Scotia; sga, Alba) was the Kingdom of Scotland between the deaths of Donald II in 900 and of Alexander III in 1286. The latter's death led indirectly to an invasion of Scotland by Edward I of England in 1296 and the ...

Background

Following the

Anglo-Saxon invasion of Britain The Anglo-Saxon settlement of Britain is the process which changed the language and culture of most of what became England from Romano-British to Germanic peoples, Germanic. The Germanic-speakers in Britain, themselves of diverse origins, ev ...

, the Kingdom of Alt Clut was the only remaining

kingdom outside of Wales. At the time of the siege it was ruled by

Arthgal ap Dyfnwal Arthgal ap Dyfnwal (died 872) was a ninth-century King of Alt Clut. He descended from a long line of rulers of the British Kingdom of Alt Clut. Either he or his father, Dumnagual IV of Alt Clut, Dyfnwal ap Rhydderch, King of Alt Clut, may have r ...

. For most of the 9th century, Alt Clut had escaped the worst of the

Viking invasions of Scotland Scandinavian Scotland was the period from the 8th to the 15th centuries during which Vikings and Norse settlers, mainly Norwegians and to a lesser extent other Scandinavians, and their descendants colonised parts of what is now the periphery of ...

. By 870, the settlement on

was the centre of a small but wealthy kingdom. The site was strategically important, commanding the confluence of the rivers

Clyde Clyde may refer to: People * Clyde (given name) * Clyde (surname) Places For townships see also Clyde Township Australia * Clyde, New South Wales * Clyde, Victoria * Clyde River, New South Wales Canada * Clyde, Alberta * Clyde, Ontario, a tow ...

and

Leven Leven may refer to: People * Leven (name), list of people with the name Nobility * Earl of Leven a title in the Peerage of Scotland Placenames * Leven, Fife Leven ( gd, Inbhir Lìobhann) is a seaside town in Fife, set in the east Central ...

. Conquering Dumbarton would make it possible for the Vikings to sail upriver into the central lowlands of Scotland. Dumbarton Rock was an extremely strong defensive position and had previously survived several sieges, including a co-ordinated assault by

Angles The Angles ( ang, Ængle, ; la, Angli) were one of the main Germanic peoples who settled in Great Britain in the post-Roman period. They founded several kingdoms of the Heptarchy in Anglo-Saxon England. Their name is the root of the name ' ...

and

Picts The Picts were a group of peoples who lived in what is now northern and eastern Scotland (north of the Firth of Forth) during Late Antiquity and the Early Middle Ages. Where they lived and what their culture was like can be inferred from ea ...

in 756. Following his successful invasion of England, including the conquest of

York York is a cathedral city with Roman origins, sited at the confluence of the rivers Ouse and Foss in North Yorkshire, England. It is the historic county town of Yorkshire. The city has many historic buildings and other structures, such as a ...

in 866,

joined forces with

, the Scandinavian

, to target this prosperous town. Aside from loot, possible objectives might have included neutralising the Britons as a maritime power. No other campaign by Ímar and Amlaíb involved such a concentrated assault in one place, providing evidence of Alt Clut's continuing power at the time.

Siege

In 870 Amlaíb and Ímar gathered their combined forces and launched their attack on Dumbarton. Unable to take the fortress, they besieged the rock for a period of four months, a length of time highly unusual for the period, and unprecedented in the history of

warfare in the British Isles. The defenders survived four months of the siege before the well ran dry, forcing them to capitulate. Accounts of the siege in Welsh chronicles describe the destruction of the summit of Dumbarton Rock. Based on these texts, historian Alan Macquarrie suggests that after a prolonged siege the Norse attackers may have seized the lower part of the rock, where the well was located, forcing the defenders to retreat to the highest craig without a water supply. Once the siege was over the Vikings plundered the fortress, taking many of the defenders captive.

Aftermath

The

Annals of Ulster The ''Annals of Ulster'' ( ga, Annála Uladh) are annals of medieval Ireland. The entries span the years from 431 AD to 1540 AD. The entries up to 1489 AD were compiled in the late 15th century by the scribe Ruaidhrí Ó Luinín, ...

record that once the siege had ended, a fleet of 200 ships transported the prisoners to Dublin. Alongside these prisoners were others, including Picts, Scots and

Northumbrians la, Regnum Northanhymbrorum , conventional_long_name = Kingdom of Northumbria , common_name = Northumbria , status = State , status_text = Unified Anglian kingdom (before 876)North: Anglian kingdom (af ...

, who had been captured by Ímar and Amlaíb in previous raids. The fate of these prisoners is not known, but with Dublin at the time being one of Europe's premier slave markets it is likely they would end up as slaves. Following the siege of Alt Clut's royal and religious centre, the kingdom moved upriver to

, while Dumbarton Rock may have become a Viking outpost for a period. After this shift the kingdom became known as the

. It is possible that Arthgal escaped the siege and sought safety in Pictland, or alternatively he may have been among the prisoners taken back to Dublin by the Vikings. In 872, Arthgal is recorded as being murdered, possibly on the advice of

Constantine I of Scotland Constantine most often refers to: * Constantine the Great, Roman emperor from 306 to 337, also known as Constantine I *Constantine, Algeria, a city in Algeria Constantine may also refer to: People * Constantine (name), a masculine given name ...

. The kingdom was severely weakened by the siege, as its main fortress had been razed and its political structure was in disarray. The finding of some Norse style ruins in the Clyde area seems to suggest that the fall of Dumbarton led to more Norse influence in the area and the opening up of the kingdom to Norse settlement. It is likely Strathclyde during this time began to fall into the sway of

Alba ''Alba'' ( , ) is the Scottish Gaelic name for Scotland. It is also, in English language historiography, used to refer to the polity of Picts and Scottish people, Scots united in the ninth century as the Kingdom of Alba, until it developed i ...

. Nonetheless, Strathclyde is documented in battles and royal records to have existed as an independent kingdom up until some point in the

11th century The 11th century is the period from 1001 ( MI) through 1100 ( MC) in accordance with the Julian calendar, and the 1st century of the 2nd millennium. In the history of Europe, this period is considered the early part of the High Middle Ages. Th ...

, when it was peacefully incorporated. The local Cumbric culture would go extinct soon after, dying out at the latest around 1300. Arthgal would be succeeded by his son

Rhun ab Arthgal Rhun ab Arthgal was a ninth-century King of Strathclyde. He is the only known son of Arthgal ap Dyfnwal, King of Alt Clut. In 870, during the latter's reign, the fortress of Alt Clut was captured by Vikings, after which Arthgal and his family may ...

, who became the King of Strathclyde after his father's death. It is likely that Rhun ruled as a subordinate of Constantine, who was his brother-in-law, providing a possible motive for the death of Arthgal.

References

Sources

* * * * * * * * * * {{cite news , last1=The Scotsman , title=Ivar the Boneless and a brutal Viking invasion of Scotland , url=https://www.scotsman.com/whats-on/arts-and-entertainment/ivar-boneless-and-brutal-viking-invasion-scotland-1460905 , accessdate=6 August 2020 , work=www.scotsman.com , publisher=JPIMedia Publishing ltd , date=5 December 2016 , language=en 870s conflicts

Dumbarton Dumbarton (; also sco, Dumbairton; ) is a town in West Dunbartonshire, Scotland, on the north bank of the River Clyde where the River Leven flows into the Clyde estuary. In 2006, it had an estimated population of 19,990. Dumbarton was the ca ...

870 9th century in Scotland