The history of Denmark and the history of the Vikings are so intertwined and intermingled that the two are inseparable. 

So how did this Northern European country fare during the age (c. 793 – 1066 C.E.) when Viking warriors roamed the oceans, seas, and rivers?

Enter the Danes

The history of Denmark, at least until the Nordic Iron Age (c. 500 BCE - 800 CE), is a subject dealt with in more detail, skill, and knowledge in a thousand books than anything we here at The Viking Herald could possibly hope to achieve. 

However, it is worth noting that any history of the Viking Age in Denmark needs a beginning.

People have inhabited what is now Denmark for the past 12,000 years. However, skipping several millennia, we land in a time when the Roman Empire stretched from the Black Sea to the Pyrenees, from the borders of Hibernia (Ireland) to the rivers of the Euphrates. 

The Roman Empire never quite made it as far north as Denmark, but there was a significant amount of trade with societies throughout Northern Europe. 

Danish warriors and mercenaries headed south to serve with the Roman legions whilst a significant amount of Roman goods and wares headed in the opposite direction.

Following the collapse of Roman security and prestige in Western Europe, the locus of power shifted eastward to the grand city of Constantinople, on the mouth of the Bosphorus River. 

There, in the 6th century CE, the writer Jordanes describes the people he calls "Dani," a tribe of Germanic peoples who lived in the southern portion of what he called "Scandza" (to us, the Scandinavian Peninsula).

Like so many peoples in the Migration Period (c. 100 – 500 CE), these Dani inhabited an area (between the rivers Eider and Schlei) that would eventually be forged into a kingdom that contemporaries called the March of the Danes, Denmark.

Boomtown cities

These Danes were similar in culture and language to the other peoples who inhabited the Scandinavian Peninsula. 

They all spoke what has been called Proto-Norse, which would, from the 8th century CE onwards, develop into the Old Norse language. This linked the Danes to their other (soon-to-be) Viking brethren further north.

Denmark's strategic position at the tip of Northern Europe and the crossroads of trade between the Baltic, Scandinavian, Russian and Frankish realms soon saw the construction and consolidation of trading towns throughout the country. 

Towns such as Aarhus, Hedeby, Ribe, and Viborg soon became bustling early medieval entrepots. Hedeby remained the largest settlement in Scandinavia until it was partially destroyed by fire in the 11th century CE.

This boom in trade went hand in hand with a different sort of expansion. By the late 8th century CE, Danish warriors soon took to the seas to begin a series of devastating raids throughout much of Europe. 

They were called Vikingr (pirates) but would go down in history as the Vikings.

People from Denmark established many northern European towns and cities. Photo: Fabian Junge / Shutterstock

The (Danish) Viking expansion

From the beginning of the 9th century CE, technological developments in shipbuilding, population pressure, and geopolitical insecurity across Europe saw Danish warriors begin a series of well-organized raids across the width and breadth of Europe. 

Much has been made about the now famous raid on Lindisfarne Island, off the northeast coast of England, in 793 CE. Yet this raid was just typical of hundreds of such raids that Danish warriors carried out, harrying parts of coastal and river communities throughout the British Isles, Frisia, and northern France throughout the late 8th and into the 9th centuries CE.

While it was Danish Vikings that first came into (often bloody and violent) contact with these communities, after a while, people from Danish society would follow as colonizers. 

Peoples from Denmark were responsible for the establishment of many northern European cities such as Dyfflin (Dublin), Limerick, and Cork, whilst they soon swarmed into the Anglo-Saxon kingdoms of East Anglia, Northumbria, and Mercia.

The Danelaw

Following initial Viking raids on the British Isles, the next phase was initiated by "the Great Heathen Army" in the mid-860s CE. 

Modern scholars have cast doubt on whether this was ever just one solitary invasion force but was more likely a series of smaller forces that joined up to wreak havoc in the Anglo-Saxon kingdoms of England. 

The politically fragmented nature of Anglo-Saxon England, a series of seven petty kingdoms (the so-called Heptarchy), meant that the invading Viking force never faced a unified front. 

As such, they could pick one kingdom off at a time until the only hope for Anglo-Saxon fightback lay with the Kingdom of Wessex in the southwest.

Whilst the initial Viking raids, and series of invasions, may well have been opportunistic, from the late 860s CE, the tide turned in favor of these (mostly) Danish warriors. Following a series of military victories, the invaders solidified and then cemented their position in England. 

This included a huge swathe of land that encompasses 15 current modern shires, from the borders of the Scottish Kingdom of Strathclyde in the north, through the English Midlands, and as far south as London.

This was the area that the locals called "Danelaw," i.e., the area where the laws of the Danes (Vikings) held sway. It would remain under the Viking sphere of influence until 1085 CE when Danish King Canute IV sacked York for the last time. 

Further afield, Danish Vikings saw significant raiding action – that often led to settlement – in Ireland, northern France (Normandy), and areas of the Mediterranean, especially the Atlantic coasts of Spain and Portugal.

According to lore, Harthacnut transformed the Danevirke into a proper medieval kingdom. Photo: Luis Abrantes / Shutterstock

A Kingdom of Earth and Heaven forged

As the Viking Age (c. 793 – 1066 CE) was now in full swing by the 9th century, the number of goods, people, and treasure flooding back into Denmark soon began to impact society. 

The small trading towns soon grew into prosperous and large cities (for an early medieval standard). A merchant class slowly emerged, and more and more warriors gained political and economic power. 

The extra money also allowed the Danevirke – a series of fortifications at the southern end of the Danish realm – to be properly manned in order to stave off attacks from the nearby opportunistic realm of the Franks.

Over the course of the next century, Frankish forces were constantly repelled, and the Danevirke fortified ever more securely, meaning that the Danish rulers must have been able to contribute a significant amount of their bulging purses to defensive measures. 

According to the Heimskringla, it was the son of the legendary Danish King, Harthacnut, who would transform this Viking realm into a proper medieval kingdom. Harthacnut may very well be semi-legendary, but his son, Gorm the Old, was not. 

Though scholars disagree exactly how he did or, indeed, on the timeline, Gorm was said to have unified the Danish people under his rule from Jelling in Jutland. He reigned for over two decades – a significant amount of time in the early medieval period – and was succeeded by his son, Harald.

The rule of Harald Bluetooth (as he was known) would mark yet another fork in the road for Danish history. Aside from seizing the Norwegian throne and ruling the two kingdoms, Bluetooth was also said to have been converted to the Christian faith and done much to introduce that religion to the pagan Danish people who still believed in the Old Norse religion. 

Though Ansgar, a missionary, is credited with introducing Christianity into Denmark, it was Bluetooth's conversion that saw, for the first time, the political elites start to adopt this new faith seriously.

The North Sea Empire

Following in his father and grandfather's famous footsteps was seemingly not a big deal for Harald's son, Sweyn.

In fact, it appears that little love was lost between Sweyn and his father since he revolted against his father sometime in the 980s, deposing him, and forcing him to flee the realm. 

By 986 CE Sweyn had deposed his father both in Denmark and, with the support of the powerful Jarls of Lade, further north in Norway too. 

At the turn of the 11th century CE, Sweyn, whose beard was said to be shaped like a fork (surely one of history's most descriptively hilariously and recognizable epithet), turned his attention across the North Sea and began a series of invasions over a decade.

A growing discontentment with the Danelaw, the Norse people, and culture, as well as the growing opportunism and strength of King Æthelstan - who was king of a people (the English) rather than any unified kingdom (as England would become later in the early medieval period), led to the famous St. Brice's Day Massacre in 1012 CE. 

This massacre, where untold numbers of Danish living in England were killed upon the orders of Æthelstan, was the pretext Forkbeard needed to invade England. 

Over the course of the next year, Forkbeard would conduct a series of campaigns against Æthelstan before finally being crowned King of England, in London, on Christmas Day 1013 CE. 

A great empire – encompassing all the Danelaw and Anglo-Saxon realms of England along with the kingdoms of Norway and Denmark – was born, united by the North Sea.

Forkbeard formed a great empire, united by the North Sea. Photo: Mikkel Graversgaard / Shutterstock

The peak of Danish Viking power?

Forkbeard had – for the briefest of times – 5 weeks – secured what later medieval Danish kings could only dream of: he had forged an empire in Northern Europe, second in size, economy, and political importance to the Holy Roman Empire. 

His untimely death would spell the beginning of the end of the Viking history of Denmark. Though his son, Canute, would regain two of the three thrones of his father's empire (Denmark and England), the great North Sea Empire was never the same again.

By the end of Canute's reign, in 1035 CE, Denmark was rapidly transforming into a medieval Christian kingdom. Though an official archdiocese was not established in Denmark until 1104 CE, by the mid-11th century CE. the conversion of Denmark was, officially at least, complete. 

What had begun as a series of raids across Northern Europe had resulted in the Danish people fighting, trading, and colonizing huge swathes of the North Atlantic World, from Greenland to Baghdad. 

A series of petty early medieval kingdoms had, through blood, sweat, and treasure, not to mention religion, been transformed into the medieval Kingdom of Denmark.

Literary Hub has published a "Shakespearean guide" for the recently released Viking movie, The Northmen, full of wonderful Danish historical context. 

It can be read here, while the National Museum of Denmark has a webpage dedicated to the Viking Age accessible here.

***King Canute's postscript: Righting a common misconception***

A final word, however, must be spared to right a historical wrong. Canute the Great, son of Sweyn Forkbeard, is often misrepresented as an arrogant king who thought he could, literally, stop the tide. 

However, this is a twisting of the proverbial reference that the 12th century CE historian, Henry of Huntingdon, wanted to paint.

Cnut did indeed take his courtiers to the shoreline, to sit upon a throne, but he wanted to demonstrate that he, despite being a powerful king, was helpless to stop the tide, a show of his good Christian piety and humility. 

He did not, as is popularly believed, command the tide to stop in a show of arrogance. So, just remember that fact the next time you accuse someone of being as pigheaded as poor old King Canute. 

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