Cnut: Why The Norse King Who Ruled England Is Known As 'The Great'

Born probably in the 990s, Cnut was the son of Swein Forkbeard, king of Denmark, and a Polish princess whose name is not recorded. Throughout Cnut’s childhood Swein carried out devastating raids on England that increasingly undermined the rule of the English king Æthelred.

In 1013, when Cnut was in his teens, Swein launched a full-scale invasion, landing a fleet of ships and forcing Æthelred to flee to Normandy. Cnut accompanied his father to England, and was left in charge of the fleet as Swein campaigned in the south. Around this time Swein, who had forged alliances with Æthelred’s enemies among the English nobility, married his teenage son to an Englishwoman. Ælfgifu of Northampton belonged to a powerful family in the Midlands, and her relatives were important allies for Swein and Cnut.

From the raid on Lindisfarne to Harald Hardrada's defeat: 8 Viking dates you need to know

By Christmas 1013 Swein was king of England, but his reign was short-lived. He died suddenly on 3 February 1014, after just a few weeks as king. Cnut was chosen to lead the Danish army in England, but he was young and inexperienced, and unable to hold on to his father’s conquered lands. The English nobles invited Æthelred to return from Normandy – on condition that he promised to be a better ruler than before – and Cnut was forced to flee back to Denmark.

In the summer of 1015, he returned to England with a huge fleet. One source describes the splendour of his ships: “So magnificent was their ornamentation that the eyes of those who beheld them were dazzled, and they seemed to be made of fire rather than of wood... The ships alone would have terrified the enemy, before the warriors they carried joined battle at all.”

Even so, it took more than a year of war before Cnut seized control of England. After Æthelred died in April 1016, the English king’s son Edmund Ironside stoutly led the defence against the Danes, and over the summer of that year Cnut and Edmund fought a series of battles across the south of England. The Danes fiercely besieged London, but failed to capture it.

The final battle was fought on 18 October 1016 at a place in Essex named as ‘Assandun’. The location is disputed, but it was probably Ashingdon or Ashdon. The Danes were victorious, and many were killed on the English side; the Anglo-Saxon Chronicle laments that “all the best of the English nation” were slain. Danish tradition said that Cnut’s troops carried into battle a magical banner embroidered with a raven that beat its wings to prophesy their triumph.

The Danes were victorious, and many were killed on the English side; the Anglo-Saxon Chronicle laments that 'all the best of the English nation' were slain

After Assandun, Cnut and Edmund agreed to make peace, dividing the kingdom between them. When Edmund died just six weeks later, on 30 November, Cnut was left as sole king of England.

Cementing kingship

In the first months of his reign Cnut ruthlessly eliminated anyone who might challenge him. The remaining members of the English royal family were killed or driven into exile, and Edmund Ironside’s wife and young children fled to Hungary.

Æthelred’s widow, Emma, had taken refuge in Normandy during these dangerous years, but in 1017 Cnut sent for her, and she agreed to marry him – her husband’s enemy. By marrying Emma, sister of the Duke of Normandy, Cnut gained an alliance with a powerful neighbour and neutralised any challenge from the children of Æthelred and Emma, who remained in Normandy throughout Cnut’s reign.

Norman women: the power behind the thrones

Cnut already had two sons with Ælfgifu of Northampton, and he did not repudiate her or their children after his marriage to Emma. However, Emma was acknowledged as his queen, and he seems to have made an assurance to her that any son she might have by him would succeed him as king. Cnut and Emma went on to have two children, Harthacnut and Gunnhild.

The first year of Cnut’s reign saw political executions and heavy taxation imposed on England, but by the end of 1017 his power seems to have been secure, and from then on he adopted a conciliatory approach to the country he had conquered. He divided England into four earldoms, appointing his loyal supporters – both English and Danish – as earls of Northumbria, Mercia, Wessex and East Anglia. In 1018, at a meeting in Oxford, an agreement was reached that declared Cnut had “established peace and friendship between the Danes and the English, and put an end to all their former enmity”. Both English and Danes agreed to follow the law-code of Edgar, Æthelred’s father, and “to love King Cnut with justice and loyalty”.

There is little evidence of rebellion in England against the Danish conquerors – certainly nothing compared to the turmoil that followed the Norman conquest

This peaceful state of affairs seems largely to have endured for the rest of Cnut’s reign. Surprisingly, there is little evidence of rebellion in England against the Danish conquerors – certainly nothing compared to the turmoil that followed the Norman conquest, when revolts continued for more than a decade after 1066. Perhaps this was because Cnut so quickly showed his intention to become almost more English than the English. He ruled through existing English laws, and promoted Englishmen as well as Danes to be his advisers and earls. Lands were given to only a handful of high-ranking Danes, who married into English families and forged a mixed Anglo-Scandinavian society.

Wooing the church

Crucially, Cnut also won the support of the English church and, under the guidance of Wulfstan, archbishop of York, the young Viking began to present himself as a Christian king. He made overtures of reconciliation towards the church, becoming a generous patron of monasteries and a devotee of English saints. He performed public gestures of atonement for the worst atrocities of his conquest, founding a church at the site of the battle of Assandun to commemorate the dead, and paying honour to Saint Ælfheah, archbishop of Canterbury, who had been brutally killed by a Danish army in 1012.

A famous image of Cnut and Emma, made in their lifetime (shown left), depicts them presenting a precious golden cross to the New Minster in Winchester. They are crowned by angels, with Christ, the Virgin Mary and Saint Peter above them and monks below. The picture shows an ideal royal couple, devout and generous towards the church. By presenting himself in this way, Cnut made himself very popular with English monastic writers.

By the 12th century there were many stories about his piety, telling how he presented his own crown to a figure of Christ, or walked five miles barefoot to the shrine of Saint Cuthbert at Durham. At Ely, it was said that Cnut so loved to visit the monastery that he composed a song in English expressing his delight at the singing of the monks:

Merry sang the monks in ElyWhen Cnut the king rowed by.

Row, men, near the land

Alet us hear these monks sing.

All of this burnished Cnut’s reputation in later medieval sources, in which he was presented as an exemplary Christian king.

But though he may have ruled England peacefully, Cnut could be severe in his other dominions. In the second half of his reign he expanded his empire into Norway, in part by bribing the supporters of his chief rival, Olaf Haraldsson. Olaf, in alliance with the king of Sweden, attempted to resist Cnut’s growing power in the north, and fought a battle against Cnut at the Helgeå river in Sweden in 1026. But those attempts were ultimately unsuccessful, and by about 1028 Norway was under Cnut’s control. He sent his first wife, Ælfgifu, and their son Swein to rule on his behalf in Norway, where they proved to be very unpopular.

Because of his extensive empire, Cnut’s court was multilingual to an extent unparalleled in pre-Conquest England

At the height of his power Cnut was king of England, Denmark, Norway and parts of Sweden, and may also have had some authority over Scotland and Ireland – a North Sea empire matched by few rulers before or since. In 1027 he travelled to Rome, where he was welcomed with honour by the pope and Conrad II, ruler of the Holy Roman Empire. He was treated as a northern emperor, and arranged for his daughter Gunnhild to marry Conrad’s son. While in Rome Cnut sent back a letter to the people of England declaring that he would never cease to devote himself to “the needs of all my people”.

The global millennium: how the year AD 1000 was more globalised than we might think

Because of his extensive empire, Cnut’s court was multilingual to an extent unparalleled in pre-Conquest England. The king’s laws and official pronouncements continued to be issued in English, but Cnut was a patron of Old Norse poetry, too; his poets praised him as “the greatest prince under the heavens”. Emma was also a patron of literature; she commissioned a Latin history of Cnut’s conquest and reign known as the Encomium Emmae Reginae (‘In Praise of Queen Emma’). Cnut’s court in England was a meeting place for people from across his empire and beyond, including Danes, Norwegians and Icelanders as well as Emma and her Norman followers.

End of Viking rule

Cnut died at Shaftesbury on 12 November 1035, aged probably not much more than 40, and was buried in the Old Minster at Winchester, the traditional capital of the kings of Wessex. His remains, together with those of other pre-Conquest monarchs, were removed from their resting-place in 1642 by parliamentarian soldiers, and are now among a jumble of bones kept in mortuary chests in Winchester Cathedral.

After Cnut’s death, the succession was contested by sons of his two wives. Harold Harefoot, one of Cnut’s children with Ælfgifu, gained enough support to become king, but died less than five years later without an heir. Harold was succeeded by Emma’s son Harthacnut but he, too, died young and childless in 1042.

During Harthacnut’s reign his half-brother Edward – Emma’s son by Æthelred – returned to England from a long exile in Normandy and on Harthacnut’s death became king. The line of the kings of Wessex had returned to the English throne, and Edward (later known as the Confessor) went on to reign for more than 20 years. His mother, Emma, died in 1052; she had been the wife of two kings and mother of two more, and had long outlived both her husbands.

Are women at the heart of the action in the Norman Conquest?

Though Cnut’s dynasty quickly died out in England, the Danish men and women he had promoted continued to influence English politics throughout Edward’s reign. Earl Godwin and his Danish wife Gytha, a close relative of Cnut, headed a powerful Anglo-Danish family who clashed with Edward and his Norman supporters at court. In 1066, when Edward died without a direct heir, the earl’s son Harold briefly occupied the English throne, while his cousin, Cnut’s nephew Swein, ruled in Denmark.

Cnut is remembered as one of the most successful kings in English history. In part this is because of the extent of his empire, but also because he managed to rule through the strong and effective systems of government and law already established in England.

There was one unexpected consequence of Cnut’s conquest: by destabilising the English monarchy and strengthening Edward’s ties with Normandy, his reign set the stage for the Norman conquest. The invasion that made England part of a Scandinavian empire in 1016 led to another, exactly 50 years later, that turned England’s political focus from Scandinavia to continental Europe. England would never again be as closely united to the northern world as it was in Cnut’s reign.

Eleanor Parker teaches Old and Middle English literature at Brasenose College, Oxford.

This article was first published in the October 2016 issue of BBC History Magazine