Danevirke
“Braver are many in word than in deed.”
– The Saga of Grettir the Strong
Legend has it that in the late eighth century Charlemagne once caught sight of some Viking ships from his breakfast table while he was visiting the French coast. His hosts assumed that they were merchants, but the emperor knew better and warned that they were “full of fierce foes”. The Franks rushed to the shore with swords drawn, but the Vikings fled so quickly that it seemed as if they had simply vanished. The disappointed courtiers returned to the palace where they were greeted with an astonishing sight. The great Charlemagne, Roman emperor and restorer of world order, was weeping. No one dared to interrupt him, but after a time spent gazing out to sea he explained himself.
“Do you know why I weep so bitterly, my true servants? I have no fear of those worthless rascals doing any harm to me; but I am sad at heart to think that even during my lifetime they have dared to touch this shore; and I am torn by a great sorrow because I foresee what evil things they will do to my descendants and their subjects.”
Although this account is obviously apocryphal, Charlemagne hardly needed any prophetic gifts to foresee the danger the Vikings posed to his kingdom. He had, in fact, been preparing his defenses against them for years, and ironically, was at least indirectly responsible for drawing the raider’s attention in the first place.
Frankish contact with Scandinavia predated him by a century or more. Viking furs, amber, eiderdown, and whetstones were highly prized in Frankish markets, and Danish merchants were common in the great imperial trading centers of Dorestad on the Rhine and Quentovic near Boulogne. With Charlemagne, however, the dynamic changed. Before him, the Franks had maintained a powerful and stable kingdom in what is today western Germany and eastern France. When Charlemagne accepted the Frankish crown in 768, he immediately began expanding his frontiers in all directions. By 800 he had seized part of the Pyrenees, Bavaria, and most of northern Italy, hammering together a larger state than any seen since the time of the Caesars. On Christmas Day that year, in a carefully orchestrated move, Pope Leo III placed a crown on Charlemagne’s head and named him the new Western Roman Emperor – an office that had been vacant for more than three centuries.
Roman style coins were minted, imperial palaces were built, and Charlemagne even considered marrying the Byzantine empress and making the northern Mediterranean a Roman lake once again. A new Pax Francia seemed to be dawning under the auspices of the all-powerful Charlemagne. Little seemed to be beyond his reach or ambition. The scholar Alcuin, who had written of the first Viking raid on Lindisfarne, hinted that the Frankish emperor even had the ability to bring back the boys / monks who had been kidnapped by the raiders.
The addition of an imperial title may have burnished the emperor’s credentials, but it also alarmed everyone on his borders. The Frankish tendency towards expansion mixed with Charlemagne’s clear ability was a dangerous combination. “If a Frank is your friend“, went a popular eighth century proverb “he’s certainly not your neighbor.”
If they didn’t think so before, by 804 the Danes would have agreed with this proverb. That year Charlemagne finally crushed the Saxons of northwestern Germany, concluding a war that had lasted for three decades. Franks and Danes were now neighbors, and the Scandinavians had reasons to believe that they were next on the menu.
The immediate cause for alarm was Charlemagne’s plans to build a fleet, something his powerful land empire had previously lacked. His stated goal was to deny Danish pirates access to the Elbe, the river protecting the empire’s northeastern flank. He had already tried to address this issue by building two fortified bridges to make it easier to move troops across at will. The other great rivers of the empire received similar treatment. A moveable bridge of pontoons connected by anchors and ropes guarded the Danube, the great eastern river that allowed access to the heart of imperial territory, and a canal was started between the Rhine and Danube to allow troops to move quickly to a threatened border.
When the emperor announced the addition of a North Sea fleet, most inhabitants of the Danish peninsula correctly suspected that Charlemagne’s real target was the Danish port of Hedeby, located just over the border on the Schlei Fjord. The town had become the great entrepôt for Viking goods, and a rival for even the largest Frankish markets. The Danes had set up toll booths and a mint – the first in Scandinavia – and were doing a brisk business that had begun to cut into the older, more established imperial trading centers.
The man responsible for Hedeby’s growth was a Viking warlord named Godfred. Frankish chronicles called him a ‘king’, but he was less a ruler of Denmark than a ruler in Denmark. Many Danes may have recognized his authority, but there were rival figures with their own halls even in the Jutland peninsula that makes up the bulk of modern Denmark.
Godfred – in what would become true Viking fashion – increased the population of Hedeby by importing captured merchants from Frankish towns he raided. To defend it against Charlemagne he began constructing the Danevirke, a massive earthen wall topped by a wooden stockade that would eventually extend across the neck of the peninsula from the North Sea to the Baltic.
Safe behind these ramparts, Godfred began to harass his powerful neighbor. He sacked several Frankish towns and forced one of Charlemagne’s allies to switch their allegiance. In response, a small Frankish army marched north and the Danevirke was put to its first test. Godfred’s soldiers held their ground, and Charlemagne, who was occupied with revolts elsewhere, decided to buy peace.
The two sides agreed that the river Eider would form a permanent border, and an apparently chastened Godfred sent hostages to the imperial capital of Aachen as a sign of good faith. This, however, turned out to be a ruse. When Charlemagne left with his army for the campaigning season early the next year, Godfred led two hundred longboats on a plundering raid of the Frisia – what is today the Netherland’s coast. His price for leaving was a hundred pounds of silver, collected from the beleaguered merchants and peasants, and whatever portable wealth his Vikings could stuff into their ships. As a final note of defiance, he announced that he was claiming the northern stretch of the Frisian coast for himself.
Despite the huge number of ships involved, the raid itself was relatively minor, and Charlemagne was too experienced to believe that any of his borders were permanent. The treaty would have been violated eventually; what really stung Charlemagne was the appropriation of a part of his empire.
It wasn’t immediately apparent how he should respond. The few ships he had were woefully inadequate for an attack, so naval operations were out of the question, and a land invasion carried its own risks. Charlemagne had just finished a bruising thirty-year war with the Saxons and, now in his late sixties, had no desire to get bogged down in another slow-burning war.
The first order of business, in any case, was to contain Godfred. The coast had to be protected, and since the Franks lacked a true fleet, the Vikings themselves would have to provide one. Independent groups of Danes had been raiding the Frankish coast for more than a decade, and the larger ones were more than happy to take Charlemagne’s gold in exchange for the promise of protection. While they protected him from the sea, Charlemagne gathered his army to storm the Danevirke.
The expedition never left. That summer, as the final preparations were being made, Godfred was cut down by one of his own men. In the chaos that followed, the identity of the killer was obscured. Some later claimed that it was his disgruntled son, angry that Godfred had recently married another woman, and others that the assassin was the king’s housecarl, but either way, the threat vanished. Charlemagne was apparently annoyed to be cheated of his revenge. His biographer Einhard claimed that the emperor remarked, “woe is me that I was not thought worthy to see my Christian hands dabbling in the blood of those dog-headed fiends.” As it turned out, Charlemagne never got the chance to wash his hands in northern gore. He expired four years later and was succeeded by his son Louis.
Without a strong hand at the helm, Charlemagne’s empire began to fall apart. At first the decay was barely noticeable. His son Louis seemed to be a younger, more cultured version of Charlemagne. The court took to calling him ‘Louis the Debonaire’, both for his refined court and his continued patronage of the arts. Even on the battlefield, he appeared to live up to his famous predecessor. During his father’s reign he had been entrusted with the security of the southwest frontier, and had been vigorous in its defense. He imposed Frankish authority over Pamplona and the Basques of the southern Pyrenees, and sacked Muslim-controlled Barcelona. All threats to his authority were ruthlessly suppressed, especially if they came from his own family. At his coronation he forced all his unmarried sisters into convents to avoid potential threats from brothers-in-law.
The promising new reign took an unexpected turn in 817, when Louis suffered a near fatal accident. A wooden gallery connecting Aachen’s cathedral to the imperial palace collapsed while he was crossing it after a church service, leaving many courtiers maimed or dead. Badly shaken, the injured Louis began plans for his succession, naming his eldest son Lothair as senior emperor, and splitting the rest between two other sons and a nephew.
The emperor recovered, but news of the planned partition had reached Italy where his nephew Bernard – currently ruling as king – discovered that he was to be demoted to a vassal. He immediately revolted, but when Louis suddenly appeared in Burgundy with an army, the unprepared Bernard surrendered without a fight. He agreed to meet with his uncle to beg his pardon, and hopefully retain Italy. Louis, however, was not in a particularly forgiving mood. Bernard was hauled back to Aachen and put on trial for treason as an example to any other family members who were considering revolt. He was found guilty, stripped of his possessions and sentenced to death.
As a sign of his clemency, Louis commuted the penalty to blinding, and two days later the procedure was carried out. The soldiers tasked with performing the blinding weren’t overly gentle. They used their heated iron rods so forcefully that Bernard didn’t survive the ordeal, dying after two days in agony.
Louis was never quite the same after the death of his nephew. Deeply religious to begin with, his guilt drove him to ever more lavish public displays. Members of the clergy became prominent advisors, and so many churches and monasteries were endowed that he acquired the sobriquet by which his most known – Louis the Pious. When even this failed to alleviate the guilt, the emperor took the extraordinary step of staging a public confession of his sins before the pope and the assembled ecclesiastics and nobles of the empire. As admirable as this conspicuous humility may have been, however, it had the effect of badly undercutting his own authority.
Contemporary society was dripping with blood. The vast frontiers were surrounded by hostile peoples who could vanish into their forests or out to sea before the imperial army appeared. A good emperor was forced to set off on at least one large military campaign a year, and failure to do so would be interpreted as weakness.
Where the emperor failed to show the mailed fist, violence flared up. Rebellions had to be met with brutal force. Captured enemies were routinely blinded, maimed, tortured, or hung. At Verdun, Charlemagne had beheaded forty-five hundred Saxon nobles as a punishment for revolt, and relocated entire populations to pacify them.
All of this was accepted as necessary behavior to impose order. When Louis, therefore, humbly bowed before the Pope and recited a laundry list of sins that included even minor offenses, it diminished the emperor in the eyes of both his subjects and his enemies. This was not the way an emperor was supposed to act. Charlemagne had wanted to bathe in the blood of his enemies; his son seemed to want to join a monastery.
On the northern frontier, the Vikings were well aware of this situation. Charlemagne’s defenses, particularly the fortified bridges and army, were still formidable enough to blunt a large attack, but there were ominous signs that the situation would soon change. A Frankish bishop traveling through Frisia found help from ‘certain northmen’ who knew the routes up the rivers that flowed toward the sea. The Vikings were clearly aware of both harbors and sea routes, and the empire lacked a fleet with which it could defend itself.
The Franks, however, seemed oblivious to the danger. Life was more prosperous than it had been in many generations, and they were enjoying the benefits of imperial rule. The archbishop of Sens in northern France, confident in the protection of the emperor, had gone so far as to demolish the walls of his city to rebuild his church. The towns on the coast were equally vulnerable. A lively wine trade had developed along the Seine between Paris and the sea, and the coast of Frisia was dotted with ports. Thanks to the Frank’s access to high quality silver – a commodity largely absent in Scandinavia – coins had replaced bartering and imperial markets were increasingly stockpiled with precious metals.
The only thing preventing a major attack was the confusion of Louis’ Viking enemies. The Danish peninsula had been in turmoil since the death of Godfred. A warrior named Harald Klak had seized power, but after a short reign had been expelled by the slain Godfred’s son Horik. Harald Klak appealed to Louis for help, slyly offering to convert to Christianity in exchange for aid. The emperor accepted, and in a sumptuous ceremony at the royal palace of Ingelheim, near Mainz, Harald and four hundred of his followers were dipped in the baptismal font. Louis the Pious stood in as Harald’s godfather.
It was a triumphal moment for several reasons. Louis was clearly not the soldier his father was, but here was an opportunity to neutralize the Danes for the foreseeable future. If Harald could be installed on the Danish throne, and then Christianize his subjects, it would pacify the northern border.
The first part of the plan worked seamlessly. Harald was given land in Frisia and tasked with defending it against marauding Vikings, while an expedition to restore his throne was gathered. With a Frankish army at his back, he was able to force his rival, Horik, to recognize him as ruler. He then invited Louis to send a missionary to aid in the conversion of the Danes. The emperor chose a Saxon preacher named Ansgar, who immediately built a church in Hedeby. At this point, however, Louis’ grand policy began to collapse.
The Danes weren’t particularly interested in Christianity, at least not as an exclusive religion. Nor it seems, were they interested in Harald Klak. After a year, he was again driven into exile by his adversary Horik, a stout pagan. To add insult to injury, Harald returned to his Frisian lands and took up piracy, spending his remaining years plundering his godfather’s property.
With the expulsion of Harald Klak, a dam seemed to break in the north, and raiders began to spill out over the Carolingian coast. Dorestad, the largest trading center in northern Europe and a main center of silver-minting, was sacked every year from 834 to 837. Horik sent an embassy to Louis claiming that he had nothing to do with the attacks on Dorestad, but did mention that he had apprehended and punished those responsible. The latter claim, at least, was probably true. Successful raiders were potential rivals, and Horik had no desire to repeat Harald Klak’s fate.
Individual Vikings out for plunder needed no invitations from the king to attack. The Frankish empire was clearly tottering. Louis’ tin-eared rule – exacerbated by an ill-thought out plan to include a son from his second marriage into the succession – resulted in a series of civil wars and his deposition at the hands of his remaining sons. Although he was restored to the throne the following year, his prestige never recovered.
The damage it did to his empire was immense. Not only were there lingering revolts – he spent the final years of his reign putting down insurrections – but the distractions allowed the Vikings to arrive in greater numbers. Multiple groups began to hit the coasts at the same time, burning villages, seizing booty, and carrying away the inhabitants, leaving only the old and sick behind.
In 836 Horik himself led a major raid on Antwerp, and when several of his warriors died in the assault, he had the nerve to demand weregild – compensation for his loss of soldiers. Louis responded by gathering a large army, and the Vikings melted away, but only as far as Frisia where they continued to raid. In 840, the emperor finally ordered the construction of his father’s North Sea fleet to challenge them, but died a few months later without accomplishing anything.
Instead of unifying against the common threat, Louis’ sons spent the next three years fighting for supremacy as the empire disintegrated around them. On occasion they even tried to use the Vikings to attack each other. The eldest sibling, Lothar, welcomed old Harald Klak into his court and rewarded him with land for raiding his brother’s territory. This turned out to be an exceptionally bad idea, as it gave the Vikings familiarity with and access to Frankish territory. Harald, and streams of like-minded Vikings, happily plundered their way across the northern coasts of the empire.
These attacks depended on speed, not overwhelming force. By the mid ninth century the typical Viking “army” consisted of a few ships with perhaps a hundred men. Some men would be left to guard the ships while the rest fanned out to plunder. In these early days they weren’t interested in prisoners, and would kill or burn anything that couldn’t be taken.
The small numbers were a vulnerability, but this was made up for by the speed of the attacks. Most Vikings were reluctant to travel far from the coasts of the sea or river systems, and generally avoided pitched battles. Their equipment was more often than not inferior to their Frankish opponents; Vikings caught in open country were usually overwhelmed. This was partially because they lacked the armor common in Europe at the time. Frankish chronicles referred to them as ‘naked’, and they had to scavenge helmets and weapons from the dead since several Frankish rulers sensibly forbade the sale of weapons to the Vikings on pain of death.
The one exception to this general inferiority were Viking swords. The original design was probably copied from an eighth century Frankish source, a blacksmith named Ulfberht whose name soon became a brand. The Vikings quickly learned to manufacture the blades themselves, and weapons bearing the inscription Ulfberht have been found all over Scandinavia. They were typically double edged, with a rounded point, made of multiple bars of iron twisted together. This pattern welding created a relatively strong and lightweight blade that could be reforged if broken. They were clearly among a warrior’s most prized possessions and were passed down as heirlooms and given names like “Odin’s Flame” and “Leg-Biter“.
Aside from their swords, the Viking’s main advantages lay in their sophisticated intelligence gathering and their terrifying adaptability. They had advance warning of most Frankish military maneuvers, and could respond quickly to take advantage of political changes. Most formidable of all, was their malleability. ‘Brotherhoods’ of dozens or even hundreds could combine into a larger army, and then re-dissolve into groups at will. This made it almost impossible to inflict a serious defeat on them, or even predict where to concentrate your defenses.
The Vikings were usually also more pragmatic than their opponents. They had no qualms about traveling through woods, used impromptu buildings like stone churches as forts, and dug concealed pits to disable pursuing cavalry. They attacked at night, and were willing – unlike the Frankish nobility – to get their hands dirty by digging quick trenches and earthworks. Most of all they could pick their prey and had exquisite timing. Earlier barbarians had avoided churches; the Vikings targeted them, usually during feast days when towns were full of wealthy potential hostages.
The Christian communities didn’t stand a chance. The monastery of Noirmoutier, on an island at the mouth of the Loire, was sacked every year from 819 to 836. It became an annual tradition for the monks to evacuate the island for the spring and summer, returning only after the raiding season had ended. Finally, in 836 they had enough and carrying the relics of their patron saint – and what was left of the treasury – they fled east in search of a safe haven. For the next three decades they were driven from one refuge to the next until they finally settled in Burgundy near the Swiss border, about as far from the Vikings and the sea as one could get.
A monk of Noirmoutier summed up the desperation in a plea for his fellow Christians to stop their infighting and defend themselves:
“The number of ships grows larger and larger, the great host of Northmen continually increases… they capture every city they pass through, and none can withstand them… There is hardly a single place, hardly a monastery which is respected, all the inhabitants take to flight and few and far between are those who dare to say: ‘Stay where you are, stay where you are, fight back, do battle for your country, for your children, for your family!’ In their paralysis, in the midst of their mutual rivalries, they buy back at the cost of tribute that which they should have defended, weapons in hand, and allow the Christian kingdom to founder.”
The monk’s advice went unheeded. By the time the Frankish civil war ended, Charlemagne’s empire had dissolved into three kingdoms, each with their vulnerabilities brutally exposed. The western Frankish kingdom became the basis of the kingdom of France, the eastern, Germany, and the third – a thin strip of land between them called Lotharingia – was absorbed by its neighbors. Viking raiding groups became larger and bolder. Instead of two or three ships traveling together, they were now arriving in fleets of ten or twelve. More ominously still, they began to change their tactics. In 845 they returned to the island of Noirmoutier, but this time, instead of the usual raid, they fortified the island and made it a winter quarters. The usual practice was to raid in the warmer months, and return home before the first snows fell. Now, however, they intended to stop wasting time in transit, and to be more systematic in the collection of loot.
Launching raids from their base, they could now penetrate further up rivers, putting more towns and even cities in range. Rouen, Nantes, and Hamburg were sacked, and Viking fleets plundered Burgundy. The next year they hit Utrecht and Antwerp, and went up the Rhine as far as Nijmegen. These raids all paled, however, before one that took place in 845 at the direction of the Danish king. He had not forgotten the Frankish support for his rival Harald Klak. Now Horik finally had his revenge.