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Your guide to King Cnut: the fierce Danish warrior who ruled England

King Cnut (also known as King Canute) is one of the Anglo-Saxon period's most prominent figures, a fierce Danish warrior king who conquered vast swathes of northern Europe and ruled over England between 1016 and 1035. Here, WB Bartlett charts Cnut's remarkable life

A 15th-century stained glass window from Canterbury Cathedral, depicting King Cnut.
Published: April 21, 2020 at 1:00 pm
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Recognised as one of the most prominent kings of the Anglo-Saxon era, King Cnut (Canute) conquered England, Denmark, Norway, and areas of Sweden. Here is everything you need to know about the Danish royal king


King Cnut: a brief biography

Born: c985–995 AD, Denmark

Died: AD 12 November 1035, Dorset, England

Ruled England: AD 1016–1035

Remembered for: Conquering kingdoms across northern Europe and becoming king of England, Denmark, Norway, and areas of Sweden.

Family: Cnut’s father was the Danish prince Svein ‘Forkbeard’, who became king of England in 1013. Little is known about Cnut’s mother, but it has been suggested that she may have been the daughter of King Mieszko I of Poland.

Cnut married Ælfgifu of Northampton (date unknown), and together they had two children named Svein and Harold. However, it has been suggested that the church did not officially recognise this marriage, for reasons that are unclear, thus Cnut was allowed to marry again.

Cnut married Emma of Normandy in 1017, and they had two children – a son named Harthacnut and a daughter named Gunhilda.


Where was Cnut born?

Cnut descended from some notable Danish rulers

The Danish royal dynasty from which Cnut descended was actually relatively young – it had been established by his great-grandfather, Gorm the Old. Gorm was a confirmed pagan worshipper who respected the old Norse gods such as Thor, Odin and Freya.

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Gorm’s son Harald was of a different disposition – he adopted Christianity and firmly established the religion in Denmark for the first time. Harald was known for an unusual distinguishing physical characteristic – his teeth appeared to be blue. This may be because they were just in poor condition and were discoloured as a result. Another possible explanation is that Harald may have filed his teeth and carved grooves in them, which he then coloured with blue dye. At any rate, he became known as Harald Bluetooth. Modern Bluetooth technology (a joint initiative between various Scandinavian companies) was named after Harald for the part that he played in trying to unify Denmark and Norway during his reign.

Harald Bluetooth was the father of Sweyn Forkbeard (who in turn was the father of Cnut). Harald and Sweyn came to blows and there was a bitter civil war between them. Harald was eventually defeated and died soon after fleeing from Denmark.

Timeline: the trials and triumphs of Cnut

c990–c1000: Cnut is born, the son of Swein Forkbeard, king of Denmark, and a Polish princess whose name is unknown

1013: Swein invades England, accompanied by Cnut, and drives the English king Æthelred into exile. Around this time Cnut marries Ælfgifu of Northampton, but is forced to return to Denmark after Swein’s death early in 1014

1015–16: Cnut returns to invade England and fights a long campaign against the English forces led by Æthelred’s son, Edmund Ironside

1016: After the battle of Assandun on 18 October, Cnut and Edmund Ironside agree to make peace and divide the kingdom between them. When Edmund dies on 30 November, Cnut is accepted as king of all England

1017: Though Ælfgifu is still alive, Cnut marries Æthelred’s widow Emma, sister of the Duke of Normandy

1018: Cnut consolidates his power in England by exiling or killing his political opponents and appointing his supporters to four great earldoms. He issues his first law-code, reaffirming the laws of his Anglo-Saxon predecessors

1026: Cnut fights a battle against the combined forces of the kings of Norway and Sweden at the Helgeå river in southern Sweden

1035: Cnut dies in Shaftesbury on 12 November and is buried in the Old Minster, Winchester

Listen: Susan Oosthuizen explains why we should be reassessing what we think about the Anglo-Saxons:


When did Cnut first travel to England?

Cnut’s first experience of invading England ended in personal disaster

Cnut grew up at a time when the crown of England was being ferociously fought over by the Anglo-Saxons and the Vikings. In 1013, he accompanied his father Sweyn Forkbeard on an invasion of England and deposed the king, Æthelred ‘The Unready’. As far as we know, this was the first time Cnut had been to the country. Sweyn was not just raiding England; by this time, he was trying to conquer it. It soon looked like Sweyn was about to become king of the country; he had been so successful in battle that the current king Æthelred had fled. But then, just as it appeared that Sweyn’s triumph was complete, he suddenly died on 3 February 1014.

Cnut, probably then just a teenager, seems to have been caught with his guard down. He assumed that he would merely assume the role left vacant by his father’s death. But he was faced by an unexpected English backlash. An army caught him unawares and a catastrophic defeat followed. Cnut barely escaped. The English nobles then invited Æthelred to return to the throne.

When Cnut left England by ship, he left behind a number of hostages – minus their ears and noses. It was a stark warning to those who did not support him that they could be in for a seriously difficult time in the future.

In 1015, Æthelred’s health deteriorated and England became divided over who should succeed the throne if he were to die. Some parts of the country allied with Cnut and the Vikings, while others showed support for Æthelred’s son, Edmund Ironside.

Silver penny depicting Cnut. (CM Dixon/Print Collector/Getty Images)
Silver penny depicting Cnut. (CM Dixon/Print Collector/Getty Images)

How did Cnut become king of England?

For a brief period in 1016, England had two kings at the same time

Opportunity arose for Cnut in 1016. Following the death of Anglo-Saxon king Æthelred ‘the Unready’, his son Edmund Ironside became king of England. However, Ironside did not have unanimous support, even from the English. Some seem to have reasoned that Cnut, who had returned to the country with a newly-raised army, was a better bet. Cnut and Edmund fought a vicious and drawn-out war. After several major clashes, the conflict’s final climactic battle was fought at Ashingdon (‘Assandun’) in Essex.

Cnut was triumphant and Ironside was forced to flee for his life. Cnut caught up with him in Gloucestershire in October 1016. However, rather than fight yet another battle, the two men agreed to divide England between them. Edmund was to have the kingdom of Wessex and Cnut the rest of England. Whether or not this unusual arrangement would have ever worked in the long-run we shall never know. Conveniently for Cnut, Ironside died just a few weeks later, on 30 November 1016, most probably after sustaining battle wounds. Cnut was now the undisputed successor to the English throne, and he was crowned at the Old St Paul’s cathedral in January 1017.

In 1018, Cnut’s brother, Harald, the king of Denmark, died, and Cnut succeeded to the Danish throne. In 1027, Cnut traveled to Scotland where the Scottish kings acknowledged Cnut as the legitimate ruler of England, bringing peace to the two rivaling countries.

Did you know?

In order to secure his position as king of England, Cnut married Æthelred’s widow, Emma of Normandy, in 1017. He also had any remaining enemies killed, and he exiled members of Æthelred’s family who were possible threats to his position on the throne.

How did Cnut deal with the issue of Viking raiders during his reign?

He forked out huge sums to get rid of raiders

‘Danegeld’ was the term used for money paid to troublesome Viking raiders, in order to make them go away. The late king Æthelred was infamous for his frequent Danegeld payments, though it was not Æthelred who made the largest Danegeld payment, but Cnut.

The idea of paying off raiders was not new; it had been used in Carolingian Francia two centuries earlier and even the heroic Alfred the Great had used it as a tactic. However, there were problems with the approach. Even if one party of raiders went away, another would soon take their place and the payments would need to be repeated, which was clearly an expensive scenario. Meanwhile, some raiders, such as Sweyn Forkbeard, might go away for a short time before simply coming back again.

When Cnut first became king, he was faced with the problem of what to do with thousands of unemployed Viking raiders. His solution was to pay them to go away. The cost was enormous – Cnut raised 10,000 Troy lbs [a measurement used to measure gold and silver] of silver from London and 72,500 Troy lbs from the rest of England to finance his policy. This was a mammoth sum at the time; while it is difficult to meaningfully convert into modern currency, it amounted to more than 30,000kg of silver. Cnut’s payment was greater than any previous Danegeld sum (the former highest was 48,000 pounds, paid in 1012 during the reign of Æthelred). But although it must have caused great pain to the taxpayers of England, the policy largely seems to have worked, as Viking raids diminished substantially.

A coin depicting Anglo-Saxon king Æthelred, who was “infamous for his frequent Danegeld payments”. (Hoberman Collection/UIG via Getty Images)
A coin depicting Anglo-Saxon king Æthelred, who was “infamous for his frequent Danegeld payments”. (Hoberman Collection/UIG via Getty Images)

How did Cnut become king of Denmark?

Cnut inherited Denmark from his older brother, not his father

At the time of Cnut’s rule, the laws of Viking succession were fairly flexible. When a great leader such as Sweyn Forkbeard died, it was not unusual for his patrimony to be divided between his sons, rather than the eldest taking everything. In theory, this helped prevent disputes involving disgruntled younger sons, though in reality these disagreements were still common.

Because Sweyn Forkbeard died while he and Cnut were in England, another of his sons, Harald, took over control of Denmark. Cnut was forced to fight for the country he was in, otherwise he would have been left with nothing. In 1018, Harald died without an obvious heir, leaving Denmark available for his brother Cnut. He seems to have taken the country without too much difficulty and held on to it for the rest of his reign.

Norway was a different matter. Although Sweyn Forkbeard had conquered the country at the end of the 11th century, it was never fully assimilated into his territories and he lost control of it after an uprising there. In 1030 Cnut won a decisive victory against his opponent, King Olaf II of Norway, at the battle of Stiklestad, but his subsequent reign in the country was short-lived. Those he appointed to be his representatives there were not popular, partly due to a period of extended famine, and they were ejected from the country. Norway was never securely integrated into Cnut’s kingdom.


Who was Cnut’s wife and what do we know about her?

Emma, Cnut's wife, was the only woman to marry two different kings of England

Emma’s first husband was the luckless Æthelred ‘the Unready’. The royal couple had several children, one of whom would later become King Edward the Confessor. When Æthelred died in 1016, Emma seems to have left the country and returned to Normandy.

When she returned to England in 1017, it was as Cnut’s wife. Emma was a loyal lieutenant for Cnut and their marriage was a great political success. Emma seems to have had a strong instinct for political survival. Cnut and Emma had several children together, including Harthacnut, who later became king of both England and Denmark for a short time.

When Cnut married Emma, he already had a partner, Ælfgifu of Northampton

However, marital alliances at the time could be complicated. When Cnut married Emma, he already had a partner, Ælfgifu of Northampton. Whether they were ever married or not is unclear. It was quite normal at that period for kings and noblemen to have a concubine rather than an official wife and it would appear that Ælfgifu fell into that category. Their relationship did produce several children. One of them, Harold ‘Harefoot’, was king of England for a short time.

Ælfgifu and Emma were bitter rivals for decades, and they both outlived Cnut.

Cnut and his wife Emma, in an engraving from an 11th-century manuscript. (DeAgostini/Getty Images)
Cnut and his wife Emma, in an engraving from an 11th-century manuscript. (DeAgostini/Getty Images)

How did Cnut view England and its people?

Despite being Danish, Cnut was an Anglophile

Cnut was an astute statesman. Rather than rejecting the former Anglo-Saxon kings of England, he went out of his way to show support for them. He did this by visiting or making gifts to shrines associated with Anglo-Saxon kings, such as Shaftesbury Abbey, where King Edward the Martyr lay buried, or Wilton Abbey, linked with St Edith, sister of Æthelred. He even paid his respects to his old adversary, Edmund Ironside, at Glastonbury Abbey. This Anglophile policy was a smart political move on Cnut’s part, as it was well regarded by his English subjects.

He also adopted a new law code, which was regarded as introducing a strong but fair regime to England. Cnut based these laws on those of the Anglo-Saxon king Edgar, whose reign was regarded as a golden age.

Cnut also not only adopted English policies, but also introduced them to his overseas territories with a good degree of success. He took full advantage of the English coinage system, which was renowned for its quality at the time. He ensured that this quality was maintained and introduced a vastly improved coinage into Denmark. There are a number of cases recorded where the moneyers working in Denmark were of English origin.

Did you know?

Cnut was praised by his contemporaries for strictly enforcing English law and justice, and he strengthened the crown’s finances by establishing new trade routes between England and Scandinavia. Cnut successfully created a unified England, and it has been suggested that he was the first English ruler to not face any internal rebellions throughout his reign.


How did Cnut use religion to bolster his power?

Cnut made his reputation as a passionate supporter of the church

Cnut was in many senses a Viking, and is probably best known as such today. He led his army using Viking tactics and launched raids on enemy territory using instantly recognisable longships. He was also fond of skalds [Scandinavian bards, or minstrels] who related old Viking sagas and tales.

Yet, it was as a patron of the church that Cnut made his reputation; this was quite a turnaround given the fact that Vikings had become renowned as scourges of the institution and frequent raiders of monasteries and other religious establishments.

This reflected the fact that these were changing times for the Viking world. Christianity had gained a foothold in much of Europe centuries previously, but was a more recent introduction to the Viking world. Cnut’s family, especially his grandfather Harald Bluetooth, had been patrons of the church. However, Cnut’s reign in England, then one of Europe’s richest countries, allowed him to take this policy to new heights. He was able to make a number of generous gifts to the church and strengthen the fledgling religion in Denmark.

Cnut’s recognition of the church reached its height in 1027, when he journeyed to Rome to attend the coronation of the Holy Roman Emperor, Conrad II. While there he met Pope John XIX. The fact that a Viking ruler could meet the head of the church and be treated as an equal of other mainstream European leaders shows just how much the world had changed.

Did Cnut really attempt to command the waves?

The tale of the king who failed to turn the tide
To many people today, Cnut is best known for the story of how he failed to command the waves. This tale has become almost proverbial as a reminder of the limits of human power and the foolishness of trying to command what is beyond one’s control. In origin, however, the story was intended to illustrate Cnut’s wisdom and piety.

It first appeared in the 12th century, in a chronicle written about a century after Cnut’s death. The historian Henry of Huntingdon says that when the king was at the height of his power he ordered his chair to be placed on the shore as the tide was coming in. When the sea did not obey his command to retreat, Cnut proclaimed: “Let all the world know that the power of kings is empty and worthless” compared to the power of God. Henry described this as a “fine and magnificent deed”.

This story is almost certainly legend, but it illustrates something important about how Cnut was remembered after his death. As a Viking king his greatest achievements were won through his dominance over the sea: his ships had conquered a great North Sea empire, and no other medieval king had such a good claim to be able to command the waves. At the same time, he gained the support of the church by presenting himself as a Christian monarch who acknowledged that his power ultimately came from God. The story of the waves astutely combines these two aspects of Cnut’s success.


When did Cnut die and who was he succeeded by?

Cnut died in Dorset, England, on 12 November 1035. The English crown was succeeded by his son Harold I. Cnut was buried in Winchester, which was the capital of the kingdom of Wessex, and his remains are now held in Winchester Cathedral.

WB Bartlett is the author of King Cnut & The Viking Conquest of England 1016


This article was first published by HistoryExtra in November 2016


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