Sweyn Forkbeard, the son of Harald, mounts a series of wars of conquest against England in retaliation for the St. Brice's Day massacre of Danes in England.

By 1014, England has completely submitted to the Danes.

However, distance and a lack of common interests prevents a lasting union, and Harald's son Cnut the Great barely maintains the link between the two countries, which completely break up during the reign of his son Hardecanute.

A final attempt by the Norwegians under Harald Hardrada to reconquer England fails, but does pave the way for William the Conqueror's takeover in 1066.

Following the death of Canute the Great, Denmark and England are left divided and despite some attempts are never reunited.

Northwest Europe (964 – 1107 CE): Norman Conquest, Insular Kingdoms, and North Sea Networks

Geographic and Environmental Context

Northwest Europe includes Iceland, Ireland, the United Kingdom, the Faroe, Shetland, and Orkney Islands, the Channel Islands, and the western coastal zones of Norway and Denmark (west of 10°E).

• Anchors: London–York–Winchester, Dublin–Waterford–Cork, Bergen–Trondheim, Orkney–Shetland–Faroe–Iceland, Channel ports (Southampton, Dover).

Climate and Environmental Shifts

• Warm conditions supported population growth; herring shoals and cod grounds underpinned fisheries from North Sea to Iceland.

Societies and Political Developments

• England: consolidation under Anglo-Saxon kings (Æthelred II, Cnut the Great, 1016–1035, Edward the Confessor).

• Norman Conquest (1066): William seized England; castles, feudal estates, Domesday Book (1086).

• Ireland: Norse towns remained semi-autonomous; Irish high-kings (Brian Boru, d. 1014 at Clontarf).

• Scotland: Kings Malcolm II–III consolidated Lowlands; Norse jarls remained strong in Orkney/Hebrides.

• Norway/Denmark: Cnut’s North Sea Empire (England–Denmark–Norway); later Norway consolidated under Olaf Haraldsson (St. Olaf, d. 1030).

• Iceland: Christianization (c. 1000), Althing maintained self-rule under Norwegian overlordship by late 11th c.

Economy and Trade

• London grew as a major European port.

• Dublin, York thrived on slave trade, silver, and hides.

• North Sea commerce: wool, cloth, salt, fish; Norwegian timber and iron traded south.

• Flemish cloth towns (Ghent, Bruges, just across boundary in Atlantic West Europe) were key markets for English wool.

Belief and Symbolism

• Christianization of Scandinavia; churches founded across Norway, Denmark, and Iceland.

• Monastic expansion in England, Ireland, Scotland; Norman Romanesque architecture flourished.

Long-Term Significance

By 1107, the Norman monarchy dominated England; Scandinavia and Iceland were Christianized; the North Sea was a connected political and economic system.

Norse traditions are slowly replaced by Christian ones in the late tenth and early eleventh centuries.

One of the most important sources for the history of the eleventh century-Vikings is the treaty between the Icelanders and Olaf Haraldsson, king of Norway circa 1015 to 1028, later known as Saint Olaf.

This is largely attributed to the missionary kings Olaf Tryggvasson and St. Olaf.

Haakon the Good had been Norway's first Christian king, in the mid-tenth century, though his attempt to introduce the religion had been rejected.

Olaf Tryggvasson, born sometime in between 963–969, sets off raiding in England with three hundred and ninety ships.

He attacks London during this raiding.

Arriving back in Norway in 995, Olav lands in Moster, where he builds the first Christian church in Norway.

From Moster, Olav sails north to Trondheim where he is proclaimed King of Norway by the Eyrathing in 995.

Sweyn Forkbeard, whose sister Gunhilde is reportedly among the victims of the Massacre of the Danes, in 1003 begins a series of retaliatory raids against England.

The Danegeld demanded and received by Forkbeard amounts to twenty-four thousand pounds of silver; a tax is collected to pay off the Danes to prevent invasion.

Thorvald Eriksson, Leif Eriksson’s brother, leads an expedition to Vinland (Newfoundland?)

in about 1004.

Legend says that Estrid of the Obrotrites was taken back to Sweden from a war in the West Slavic area of Mecklenburg as a war-prize.

She was most likely given by her father, a tribal chief of the Polabian Obotrites, as a peace offering in a marriage to seal the peace with King Olof Skötkonung, and she is thought to have brought with her a great dowry, as a great Slavic influence is represented in Sweden from her time, mainly among craftsmen.

Her husband also has a mistress, Edla, who comes from the same area in Europe as herself, and who was possibly taken to Sweden at the same time.

The king treats Edla and Estrid the same way and has given his son and his two daughters with Edla the same privileges as the children he has with Estrid, though it was Estrid he had married and made Queen.

Queen Estrid is baptized with her husband, their children and large numbers of the Swedish royal court in 1008, when the Swedish royal family converts to Christianity, although the king promises to respect the freedom of religion—Sweden is not to be Christian until the last religious war between Inge the Elder and Blot-Sweyn of 1084-1088.

Sweyn Haakonsson, after the battle of Svolder in the year 999 or 1000, becomes, with his half-brother, Eric Haakonsson, governor of Norway under Sweyn Forkbeard of Denmark.

The son of earl Hákon Sigurðarson, Sweyn is first mentioned in connection with the battle of Hjörungavágr, where the Heimskringla says he commanded sixty ships.

The written sources mentioning Sweyn are all written over one hundred and fifty years after his death.

The Swedish historian Staffan Hellberg in 1972 will claim to be able to show that Sweyn was a fictitious person, and that he had never lived.

The debate about this will form part of the wider debate about the value of the twelfth and thirteenth century sagas for eleventh century history and earlier, and is an example of the saga skepticism, particularly widespread in Swedish academia.

Hellberg's conclusions remain speculative.

Ireland’s High King Brian Boru divorces Queen Gormflaith some time during the 1010s, and she begins to engineer opposition to the High King.

Relations between Brian and Leinster have become so strained that revolt breaks out among the Leinstermen around 1012.

Eric Haakonsson leaves Norway in 1014 or 1015 and joins Cnut, later known as Canute the Great, for his campaign in England.

The Scandinavian invasion fleet lands at Sandwich in midsummer 1015 where it meets little resistance.

Cnut's forces move into Wessex and plunder in Dorset, Wiltshire and Somerset.

Alderman Eadric Streona assembles an English force of forty ships and submits to Cnut.

The Scandinavian army moves over the Thames in early 1016 into Mercia, plundering as it goes.

Prince Edmund attempts to muster an army to resist the invasion but his efforts are not successful.

Cnut's forces continue unhindered into Northumbria where Uhtred the Bold, earl of Northumbria, is murdered.

The great north English earldom is given by Cnut to Eric after he wins control of the North.

The invading army turns south again towards London.

King Æthelred the Unready dies before they arrive, and Prince Edmund is chosen king.

The Scandinavian forces besiege London.

After several battles, Cnut and Edmund reach an agreement to divide the kingdom, but Edmund dies a few months later.

Cnut, as the undisputed king of all England in 1017, divides the kingdom into four parts.

Wessex he keeps for himself, East Anglia he gives to Thorkell, Northumbria to Eric and Mercia to Eadric.

Cnut has Eadric executed as a traitor later in the same year.

…Winchester, and …

…Bath submit to Sweyn on his march south.