Vikings in Britain: how did raiders and marauders become lords and kings?

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When did the Vikings first come to England?

In Britain and Ireland, the age of Norsemen had begun gradually. The first Viking activities were surprisingly small, but they were deadly and had an impact far beyond their size. Flotillas made their way across the North Sea to raid coastal and estuarine sites, particularly monasteries, chocked full of treasures as a result of an eighth-century economic boom.

Those who embarked on the raids were the happy beneficiaries of developments in maritime technology, which allowed them to set out from Scandinavia confident of being able to return safely again. Though, like other ships of the age, they could be rowed, Viking ships enjoyed beautifully rigged square sails; they had strong keels and well-designed hulls.

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It has even been argued that Vikings had developed their navigation skills well in advance of other European peoples. While many early medieval ships used coastal routes to travel between lands, the new longships could dominate sea roads across open water, perhaps even as early as the 780s and 790s. Writing of the earliest datable Viking raid on the famous monastery of Lindisfarne in June 793, one churchman wrote of surprise “that such an inroad from the sea could be made.”

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The writer was Alcuin, formerly a deacon of York Minster, who had risen to become Charlemagne's right-hand man. Although he was some 500 miles away in the Frankish court, Alcuin conveys some of the sense of the shock of hearing the news of pagan raiders' actions. To many Christians, the Vikings heralded the apocalypse.

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The Anglo-Saxon Chronicle, a year-by-year record of events associated with the kingdom of Wessex, reported that the Vikings' arrival was preceded by freak atmospheric conditions – "dragons" were seen flying across the sky – and indeed one gravestone found at Lindisfarne shows heathen barbarians in apocalyptic terms: the Sun and the Moon, portents of the End of Days when the Sun would turn to darkness and the Moon turn a blood red, are juxtaposed by an image of seven warriors, most of whom brandish surprisingly realistic contemporary weapons. Whoever buried that member of the Lindisfarne community evidently thought that a message had been sent and had to be heeded.

In these early raids, it was speed and surprise that brought success. Where Vikings are known to have faced opposition, such as down the coast from Lindisfarne, perhaps after a raid on the monastery at Jarrow in 794, local forces could match them effectively.

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Anglo-Saxon kingdoms themselves had their own share of hardened warriors, whose whole lifestyle was organised towards the defeat of their enemies, and so they were no pushover. But with armies organised for battles fought according to rituals and expectations (at particular places and perhaps even at particular times of the year), they were rarely able to catch more mobile enemies. As one historian aptly put it, the Vikings did not “play by the rules”.

When did the Vikings settle in England?

In Britain, it all changed when Vikings stopped being summer raiders and stayed for longer, a strategy they had already been adopting in Ireland. Up until around the 850s, a local population could expect Viking war bands to go away at the end of the summer once the raiding season was over; now, the people were stuck with the enemy at large.

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The Anglo-Saxon Chronicle refers to a "Great Viking Army". The Vikings were showing that they were more than bunches of bearded marauders, but could adapt to learn lessons. Viking forces banded together, tied up their ships and dug ditches and even ramparts to protect themselves. That way they could range further and even take over territory.

The defence of the kingdom of Wessex by Alfred the Great is perhaps the best remembered and most celebrated moment of this period. The other three Anglo-Saxon kingdoms, Northumbria, Mercia and East Anglia, had lost their native rulers, only for them to be replaced by either puppet rulers or by Vikings themselves, but Wessex remained unconquered. The peace treaty that Alfred had negotiated in 871 was exchanged for silver, suggesting that Alfred survived the 870s only by the skin of his teeth.

In 878, the kingdom was briefly taken over by Vikings, but Alfred’s return to power showed an iron will. There were enough lords in England willing to choose him rather than a Scandinavian lord, and Alfred evidently worked hard to retain their support. But this was no mean feat.

The presence of powerful Scandinavian warlords in the south of England deepened the fissures of political rivalries. A charter from around this time records the confiscation of land from an ealdorman (governor) of Wiltshire, who had “deserted” both “his lord King Alfred” and his “country”, while Alfred’s own nephew, the son of his predecessor King Æthelred I (died 871), made common cause with Vikings following Alfred’s death.

What happened after Alfred the Great's death?

Alfred had held Wessex for his direct descendants to ensure that it would be the heartland of the English kingdom that was to develop during the tenth century. In Scotland, a similar pattern emerged for the descendants of the famed Kenneth MacAlpin (Cináed mac Alpín), whose kingdom of Alba was established in the vacuum created by the destruction of the power base of the western kingdom of Strathclyde in a particularly vicious Viking attack in 870. But if more powerful kingdoms developed, they had to contend with Vikings as a political force in Britain and Ireland.

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A large part of what is now England and much of northern and western Scotland, as well as the Isle of Man and land around the coast of Ireland (Dublin being one of the key examples), became home to Scandinavian settlers, with new Viking lords taking the resources of the local people, which had once been enjoyed by Anglo-Saxon, Pictish and other native rulers.

Political control was now the name of the game, and though Wessex had survived with a native dynasty, Scandinavian interests provided a fierce rivalry. The kingdom of York, controlled for generations in the mid-tenth century by competing dynasties with links to Norway, Denmark and Ireland, is the best example of the change, and the kingdom’s importance in the tenth century determined the way in which the kingdom of England developed during the course of that century. Until York and its hinterland were finally pulled into the orbit of Wessex dominance following the death of the infamous Erik ‘Bloodaxe’ in 954, Dublin, York and Scandinavia were part of an archipelago of trade and cultural connections that stretched from the Irish Sea across the North Sea and indeed further, with the Vikings’ connections to the Baltic, Eastern Europe and Russia.

Did any Vikings convert to Christianity?

During this time, many Vikings became converts to Christianity. Though pagan beliefs lingered, and indeed in some places Christ became just one of the many deities to whom one might turn, the adoption of Christianity across the Viking world was what laid the path to political and social change. The change wasn’t instant, but importantly, conversion was what allowed such things as a Christian king in England to marry his sister to the ruler of the Viking kingdom. Æthelstan, ruler of Wessex and Mercia, did just this in 926, while his other sisters were married to rulers across Europe. The Vikings were plugging into the Christian world.

In this manner, new invasions of England, spearheaded by the Danish king Sweyn ‘Forkbeard’, who was active in England in the 990s and the early years of the 11th century, were the work of a Christian prince – more like the invasion of William the Conqueror in 1066 than the depredations of the Great Viking Army in 866. Sweyn was king in Denmark, with a fleet of royal vessels and an army he could call on like the ‘feudal’ armies of later generations. But something of the Viking remained. William of Normandy had a legitimate claim to the English kingdom, however shaky. If Sweyn had any claim to England, it was a poor one and no contemporaries made anything of it, even if only to deny it. Those who came to England with Sweyn might answer a royal call, but they also came as Vikings because of the opportunities offered by belonging to a massive Viking fleet.

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Æthelred was taxing his subjects heavily in response to new Viking raids. The Anglo-Saxon Chronicle recorded the amounts increasing in response to each new outrage, from £10,000 pounds (an enormous amount for 991) to £16,000, to £24,000, then to £36,000. Some of the money was given to Vikings to go away; other sums were paid to groups of mercenaries to take service with the English king.

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Such amounts were unsustainable. In 1013, Æthelred was driven from his kingdom and Sweyn acclaimed king by his men. It looked as though he would be the first Viking king of England, as many in the south of England had already surrendered to him, handing over hostages that were then entrusted to his son Cnut, who had accompanied Sweyn from Denmark. The crowning was not to be. Sweyn died in February 1014. Æthelred was recalled from exile by his nobles and Cnut departed for Denmark, pausing only to brutally mutilate the hostages whose care he had been charged with. This was Viking politics at its most savage.

When did Cnut become king of England?

It was also typical of early medieval politics that a brutal act was called for in difficult circumstances. Cnut was in a tight spot, and he had to respond in a fashion that sent a message to those who he saw as betraying him. When Cnut returned to England with a vengeance in 1015, he took full advantage of the messy politics of Viking-Age England. He had a fleet with him once more, but he was also linked by marriage to the powerful family of the midland noblewoman Ælfgifu of Northampton. To such groups, King Cnut would have been more a native lord than an invading newcomer.

When Cnut was crowned in 1017, he must have seemed like the only sensible option for the English nobility. There was an irony here, as his father had caused so much of the upheaval and Cnut had played no small part, but this was not alien to the 11th-century game of thrones.

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Cnut was not some pagan newcomer to Christianity, freshly converted. He was part of a royal family that had been Christian for three generations. Following the death of Æthelred’s warlike son Edmund ‘Ironside’, and the exile to Normandy of other sons of Æthelred, Cnut was able to present himself as a legitimate English king. He married Queen Emma, widow of Æthelred and sister of the Norman duke, which gave Cnut the opportunity to whitewash himself with a sense of legitimacy, keeping the ambitions of the exiled princes in check, to boot.

Behind this, however, was the naked reality of power as well as pragmatism, not just on Cnut’s part but on those who accepted him as king, such as the powerful Archbishop of York, Wulfstan, who, like Alcuin, had seen the end of days coming with renewed Viking attacks.

Unlike Alcuin, Wulfstan was now accommodating himself to the new order. We can only imagine the eyebrows raised at the news that though Cnut had married Queen Emma, he had not given up his relationship with Ælfgifu. But if Ælfgifu was in Scandinavia and helped Cnut to keep connections there, where new Viking threats might arise from, an English audience might be willing to overlook a few transgressions. Sweyn’s kingdom of Denmark was in the hands of Cnut’s brother Harald, but Cnut still had a fleet behind him, which he maintained in England for two years after the death of Edmund.

Much of the fleet was dismissed in 1018, again with a massive payment of geld, but Cnut retained the services of 40 ships. Following Harald’s death around 1018, the kingdom was now Cnut’s for the taking and these ships seem to have been important in the campaign. The tables had turned. As king of England, Cnut could now be a Danish king.

From that Danish base, Cnut reclaimed the Norwegian territory that had been subject to his father. Though control of Norway remained a problem for Cnut just as it had been for Sweyn, Cnut was able to make good his claim, ruling Norway through his wife Ælfgifu and their son until 1034. The Scandinavian empire broke up, but the control of this empire was to play a key role in the downfall of the English kingdom in 1066.

When did Viking rule in England end?

Harald Hardrada (‘hard ruler’) of Norway presented himself as the heir to the Danish possessions of Cnut’s son Harthacnut, making claim to England in the aftermath of the death of Edward the Confessor with an invasion of the north of England in September 1066. After an initial victory at the gates of the great Viking city of York, Harald’s Viking strategy was decisively beaten by his namesake, Harold II of England.

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The last great battle of the Viking age had been won by an English kingdom that had spent so long fighting the Viking threat, but it was a very different kingdom from that of Alfred, given that the king who fought that battle was part of Cnut’s family through marriage. A final twist of fate was that the kingdom was lost as a result, with the Norman Conquest a few days later. Though no-one knew it at the time, Britain’s Viking Age was over.

How much of Britain was ruled by Vikings?

The clearest ‘Viking’ division in Britain is along a line from north of London, running northwest along Watling Street across England, following a treaty made between Alfred the Great and the Viking leader King Guthrum in the wake of the Battle of Edington in 878.

To the north and east of that line, Viking place-names (ending in the likes of ‘-by’ and ‘-thorpe’) appear every few miles, suggesting that some settlements were dominated by Norse-speaking lords and perhaps even settled by migrants from Scandinavia, who settled in the wake of the Great Army’s campaigns in the middle of the ninth century.

York, which was taken over by the Great Army in 866, was an early centre of power, whose hinterland seems to have been settled quickly by new Viking lords who took over (and may have re-named) Anglo-Saxon estates.

Elsewhere in England, Lincolnshire and East Anglia – whose connections across the North Sea played an important role in their prosperity – were key areas of Viking settlement. In the northwest, particularly in Cumbria, it has been argued that the settlements of Vikings were from Norway and Ireland.

Along the coast of South Wales, a few Scandinavian place-names can be found (the best example being Swansea, ‘Sweyn’s Island’) suggesting settlements there, in the Irish Sea world dominated by the Vikings of Dublin, were associated with coastal navigation, though there is no clear evidence of permanent settlement in this area.

Excavations on the island of Anglesey, on the coast of North Wales, have revealed what has been suggested as a fortified Viking encampment at Llanbedrgoch, complete with the skeletons of victims of some violent activity (perhaps even Vikings themselves).

Further north, in the Irish Sea, the Isle of Man appears to have been wholly and permanently taken over by Vikings, perhaps by the early tenth century; there the Viking legacy is deep-rooted. The annual parliament, the Tynwald, has its origins in the Viking thing (assembly), and its claim to be the longest continuous parliamentary assembly in the world is a good one.

In the north of Scotland, an area subject to kings of Norway (Orkney and Shetland were only ceded to the Scottish crown in 1468 and 1469 respectively), the types of boat burial in the area suggest cultural links with the northern Scandinavian world

Ryan Lavelle is a professor of Early Medieval History at Winchester University, and a historical advisor on the television series The Last Kingdom. His books include Cnut: The North Sea King (Allen Lane, 2017)

This content first appeared in the October 2017 issue of BBC History Revealed