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Nov. 13, 2021

64: The Great Heathen Army

64: The Great Heathen Army

A massive army of Odin-worshippers sail down the Seine and threaten Paris. With the Carolingians gone the Franks will have to fend for themselves.


When last we left off in the political narrative Emperor Charles the Bald died after nearly reuniting the Carolingian Empire. From his base in West Francia he conquered Italy, then Lotharingia and marched east to conquer the German lands. A disastrous battle forced him to retreat, and the empire remained fragmented. Before we move forward with this tale we have to look backward because there are three loose threads which in their time will play a huge role in what follows.

Our first loose thread deals with the legacy of Robert le Fort, Robert the Strong. In the 850s Robert moved his family westward, defecting to Charles the Bald who gave him honores to Marmoutier alongside other important holdings in the north. Robert led local aristocrats to resist the advances of Ludwig, the Vikings and the Bretons. Then in 858 King Charles put his son Louis the Stammerer in control of Neustria. This, combined with a marriage alliance with the Bretons, infuriated Robert who saw his power shrink. That year was Charles’ greatest challenge: Robert led a rebellion of nobles in the north, the pretender Pippin II launched a rebellion in the southwest, Vikings attacked and Ludwig invaded. Charles survived this crisis and pacified Robert, though he must have kept a careful eye on this powerful, headstrong warrior. Robert spent the 860s fighting for his king against Vikings, Bretons and incursions by Ludwig until in 866 he died fighting a Danish raiding party at the Battle of Brissarthe. That day King Charles lost a double-edged sword, as Robert was both a mighty ally who regularly held the enemies of West Francia at bay and a serious threat who could lead his fellow nobles against their own sovereign. When Robert died Charles redistributed most of his honores away from his house, depriving Robert’s thirteen-year-old son Odo the same power his father had. But the young Odo still held some noble titles and because of his father he was one of the best-connected aristocrats in the north.

The second loose thread has to deal with a prince’s love affair. In 862 King Charles’ son Louis the Stammerer turned 16 and he decided to do what all headstrong royal medieval youth do when they look to prove themselves: he rebelled against his father. To undercut his father’s powerbase in the southeast and secure his own future Louis took Ansgarde of Burgundy as wife. Depending on the chronology she either fell immediately pregnant or within two years and gave birth to a son who Louis named…Louis. Because the Carolingians are bad at naming children. Later on she gave birth to a second son, Carloman, which is slightly more creative. Charles defeated his son’s rebellion and brought the youth down to earth in a big way. Only so much written material survives so we can only guess at Louis’ mindset; likely, Louis had rebelled to prove himself since he was perpetually weak and sickly. His father easily defeated him and Louis was effectively humbled for the rest of his relatively short life.

In 870 Charles recognized that he had strong support in Burgundy but not enough in the north and ordered his son to cast aside Ansgarde in favor of Adelaide of Paris. Louis balked at the idea of turning away the mother of his children, as did Bishop Hincmar of Reims who opposed divorce in virtually every case. But Charles was determined and he argued that this was not a divorce but an annulment of a false marriage since they were wed without their father’s permission. Charles wrote to Pope John VIII and he agreed that the marriage was invalid. Now what could Louis do, when the king and Christ’s vicar on Earth claimed the marriage wasn’t legitimate? Louis bowed to pressure and put aside Ansgarde in favor of Adelaide. In a few short years Adelaide gave birth to a baby girl, though she produced no male heir while Louis still lived.

The final thread we have to discuss is the person and legend of Viking warlord Ragnar Lodbrok. Medieval sources are usually unreliable as they are fragmentary and written for specific patrons with biases in mind. Medieval Viking sources are even less reliable as they intermingle myths with their history. Historians are unsure if Ragnar was actually present at half of the events the sagas ascribe to him; there’s even questions over whether he was even a real figure. Moreover, non-Viking sources recording Viking attacks are poor as they often describe raids but not who was raiding. With all that said, for a man who might not have existed he had a profound impact on history.

Ragnar’s most famous exploit was the sack of Paris in 845. On his way up the Seine he hanged 111 Franks on an island as a sacrifice to Odin and a sign to beware his fury. King Charles arrived with an army but Ragnar repulsed his forces. With no other option, Charles paid him 7,000 pounds of silver to leave the city. Raids continued across West Francia but Charles kept getting stronger and better able to defeat or pay off the attackers. In response more Vikings chose to raid the British Isles. Ragnar himself raided Northumbria in 865 but was captured and thrown into a pit of snakes.

When news of Ragnar’s death reach Scandinavia three of his sons gathered a fleet and sailed to England to take advantage of the disunited Anglo-Saxon kingdoms. Thousands of Danish marauders plundered the east, until they met King Alfred of Wessex who initially paid them off before winning a great victory at the Battle of Edington in 878. Between the initial invasion in 866 to their defeat in 878 the Vikings had plundered much of the north and east of England. Meanwhile Francia had been relatively unscathed as Emperor Charles consolidated his power and enhanced the country’s defenses. But in 877 Charles died and the Vikings knew every time a Carolingian king died, chaos ensued. With England offered diminishing returns, Francia was back on the menu.

These three stories serve as the backdrop for today’s drama which begins with Charles the Bald’s death in 877. Louis the Stammerer recalled Hincmar, who had fallen out of favor with Charles, and the venerable bishop crowned him at Compiègne. As is natural, the new king bestowed honores on his nobles. But every honor given to one noble was a slight to another and factionalism grew in Louis’ court. Bishop Gauzlin of Paris, Conrad of Paris and Bernard of Gothia led one faction while Hugh the Abbot, Boso of Vienne and Bernard of Autun formed the other. Louis favored Gauzlin’s faction, perhaps because it was mostly based in the north, while Hugh and Boso’s faction was based in Burgundy.

King Louis was consistently sick throughout his reign. In summer 878 he fell ill at Tours and many thought he would die. He survived, and on 7 September Pope John VIII crowned Louis anew, though he refused to crown his wife Adelaide of Paris due to their close kinship, which he viewed as incestuous. Seemingly knowing his reign would be short, King Louis held a council with the King of Saxony Ludwig der Jüngere. That’s Louis the Younger in English, but as usual I am sticking to German names for the German-speaking Carolingians because otherwise everyone is named ‘Louis.’ Case in point: King Louis the Stammerer convinced Louis the Younger to honor his sons Louis and Carloman’s right to succession. The agreement could not have come at a better time, because the following Spring while campaigning against Viking raiders King Louis fell ill and died on 10 April 879 at the age of 32. He was succeeded by his two sons by his first wife Ansgarde. Though, as a short footnote for later events, before he died he did impregnate Adelaide of Paris and five months after his death she gave birth to a son, who she named Charles.

Louis reigned a mere 16 months before passing the crown to his 14 or 16 year old son Louis III and his 13 year old brother Carloman II. Immediately Charles’ regnum erupted into infighting. One faction of nobles argued that Louis III should be the sole king, while another wanted both sons to ascend the throne, dividing royal power and granting aristocrats more access to the royal personage. The dual-monarchy group won when they enlisted Ludwig der Jüngere’s assistance in exchange for Lotharingia, which the two kings formally agreed to in February 880 at the Treaty of Ribemont, the last great partition of the Carolingian Empire by Carolingian kings. I should note that the Treaty did more than just divide up Lotharingia. Karl der Grosse, Charles the Fat, inherited the northern half of Italy, while his brother Ludwig der Jüngere ruled over Lotharingia and the German East. If you’re wondering what happened to the third son of Ludwig II, he had a stroke and left his regnums to his two brothers. Bad for him, but it simplifies our map. To repeat, Louis III and Carloman II ruled West Francia, Ludwig der Jüngere ruled over Lotharingia and the east, and Karl der Grosse ruled Italy. Got it? Ok good, because now it’s going to change a little. Sort of. Not really.

In 879 while the nobility of West Francia fought over how many kings they were going to have, Count Boso of Vienne decided to make his move. In October he called together a synod of the local nobility and had himself declared King of Provence. This was an absolutely shocking development. For the first time since 751 someone not belonging to the Carolingian dynasty claimed kingship within the Carolingian Empire. Boso’s existence became a direct challenge to the entire foundation of the empire, which held that the descendants of Charles Martel were the legitimate rulers of the empire, ordained by God to lead, protect and correct Christendom, as confirmed by numerous popes. The four Carolingian kings could not allow this pretender to last. They especially wanted to put down any potential claimants to the throne outside the Carolingian house because by 880 none of them had legitimate male offspring. Louis III and Carloman II were teenagers, Ludwig der Jüngere’s only adult son died in 880 fighting against Vikings and Karl der Grosse’s only son Bernard was illegitimate. The Carolingian household was literally failing. Until these men could get busy making babies a succession crisis was inevitable, and revolts like Boso’s had to be quashed.

The four Carolingian kings met in a series of summits wherein they agreed to territorial divisions of the empire and agreed to mutually recognize each other’s children. After decades of infighting the Carolingians were finally coming together to face a mutual enemy. Then they marched into Provence, where Boso’s support evaporated in the face of this joint invasion. Boso held up in his fortress at Vienne, the only area he exercised any authority over. The four kings laid siege to the city but medieval siege equipment being what it was it was largely ineffective and the Carolingians had to retreat that winter. Boso survived, but he was now just a king of a mid-sized city.

In the meantime, Louis III had to contend with his own Great Heathen Army. During most of his grandfather Charles the Bald’s reign, the Vikings preferred to raid vulnerable areas and sail far away before a large army could arrive. But by 881 the Vikings had established themselves, setting up fortifications across Frisia and in northern Francia so that they could raid further south. In a rare occurrence, a Viking army met the Franks in a pitched battle at Saucourt-en-Vimeu. The annals record at least 9,000 Vikings were present at the battle, and while this is an exaggeration, even if there were only a quarter that number there was still an army of 2,000 Northmen, a sizeable figure for that day. Louis III, who was then only 16 or 18 years old, led the Franks against them and won decisively. Louis III’s popularity among the soldiers and his people soared and his deeds inspired the High German poem Ludwigslied, “The Lay of Louis.”

Louis III more even than most teenagers felt he was invincible. He proved himself in battle, he was beloved by his people and the poets sang of his bravery. He was riding high on his horse. Literally. On 5 August 882 Louis III was riding his horse, chasing a noblewoman back to her family mansion when he hit his head on the door lintel, fractured his skull and died. Louis III became the first but not the last French king who was killed by a doorframe.

Carloman II became sole ruler of West Francia while his uncle Karl der Grosse became king of the rest of the empire when Karl der Jungere died of illness. Now there were only three legitimate Carolingian men alive, the third being Adelaide of Paris’ three year-old son Charles. The House of Charles Martel was in dire straits, though there was some good news during that horrible year. That fall Karl der Grosse’s subjects took the city of Vienne. Boso was left alive and even still claimed to be king, but he was a relatively weak figure who only ruled a devastated city and its immediate environs.

Carloman II did what he could but the young king faced a whole new wave of large-scale

Viking assaults. On 12 December 884 the King of West Francia was killed in a tragic hunting accident. By pure coincidence and through utterly no work of his own Karl der Grosse was now Emperor of all the vast lands Charlemagne conquered. Life is funny sometimes. Under different circumstances I’m sure Karl would have loved being emperor, but he faced unprecedented attacks on his kingdom from the furious Northmen. In the prior three years Vikings had sacked the imperial palace at Aachen and numerous other major cities. There was a war in Pannonia, Hungarians assaulted the eastern frontiers and there was always the threat of an aristocratic revolt. Karl was not a bad ruler, but he was not of the same quality as Charlemagne or even Charles the Bald. He was an average ruler in a time of crisis, which, as history shows is always a dangerous combination.

On 20 May 885 Karl took up the crown of West Francia in Grand. He was an unpopular figure who seemed out of place in the west. Given the strange turns Karl’s life had taken, pretty much anywhere he was he seemed out of place. Karl was born in Alemannia and spoke German as his first language. By sheer happenstance he inherited the Kingdom of Italy. Now he was in West Francia among subjects he was least acquainted with. Still, Karl did his best to engender their love and issued a flurry of capitularies. Likewise, he tried to form connections with regional leaders, perhaps the most important of which was Odo. The son of Robert le Fort was making a name for himself and used his connections to win recognition in the north until, in 882 he was made the Count of Paris. Odo was probably the most powerful man in Western Francia, save only for the Emperor himself. Karl probably courted Odo as he hoped that through him he could keep his nobles in check. Any meeting they might have had did not last long though, as the emperor left for Italy to put down a rebellion.

Even with the Emperor far away and no king in the west, the people of Paris must have felt secure. The medieval cityscape was centered on Île de la Cité, which was surrounded by strong Roman walls. It had two bridges going to the north bank, one of stone and another of wood. The deceased king Charles the Bald had ordered every bridge in his kingdom to have towers to guard against Viking incursions, so, in addition to the city walls, the bridges had their own towers, one of stone, the other of wood. These probably also had walls or a turret and were like small fortresses. Thus, on 25 November 885 the people of Paris woke up as they normally did, convinced that their fortifications and the relics of their saints would keep the city safe. Their faith was tested that day, for sailing up the Seine was an uncountable fleet of ships with dragon maws at the helm, Viking round shields adorning their sides. The chronicles record 700 ships, carrying 40,000 men. Even though this is doubtless an exaggeration, the Viking horde that approached was certainly even greater than Ragnar’s army which sacked Paris a generation ago. With the Emperor gone, a great heathen army had come to sack the jewel of Francia.

Or so the nobility thought as they prepared for battle. The Vikings landed on the nearby shores and set up camp across from the city. From the walls, the defenders of Paris measured the full might of the enemy, knowing it was impossible to face them in open combat. After two days their leader Sigfred approached. He was let in and ushered to meet Bishop Gauzlin who was in charge of the city’s defenses. There he addressed the bishop in front of an assembly of nobles, among them Odo. According to a later poem, the Viking warlord announced, “O Gozelin, show pity to yourself, Lest you should die; obey our words, Indulge our wish: allow us only to pass.” Sigfred did not demand the city open its gates or offer tribute; instead he wanted command of the two fortified bridges so that his fleet could sail to Burgundy, which had not been ravaged by Viking raids as much as the north. But the Parisians feared his words all the same. If he spoke truly, then the fleets would ravage their countrymen, including some of their own estates, since at least a few lords in Paris had landholdings down south. If they opened the gates to the Northmen they would bring eternal shame on themselves and their city and when the Vikings inevitably attacked Paris who would rush to their defense? Moreover, what if Sigfred was lying to them? What if they turned over the bridges to the Vikings and they decided to attack the city? The Parisians would be surrendering their outer defenses without a fight.

With a poet’s flourish, Abbo recorded, that Gauzlin responded “This realm should not, because of Paris, be destroyed, But preserved by it and ever be in peace. If these walls had been granted you, as they now are, to us…what would you pledge?” To which Sigfred replied, “My head, in honour of my sword – that’s worthy of the dogs.” Then Sigfred left and the Parisians prepared for battle.

The following morning the Vikings launched a furious charge at the stone bridge. The Parisian nobles raced out to save their outer defenses, among them Odo and his brother Robert. Odo was 28 and had probably faced down Vikings many times before as he coordinated his fellow northern nobles like his father before him. Robert was 19, and while still a man, this was perhaps his first time in pitched battle. The brothers fought furiously and with their fellows repulsed the Danes, whose bodies stained the Seine red. But such was the wrath of the Northmen that many of Paris’ defenders fell, and the stone tower was badly damaged. When night fell the Vikings retreated back to their camps while the Parisians desperately rebuilt the tower’s top, replacing the fallen stone with wood. The following day the Danes launched another charge, and assaulted the wooden tower with catapults. Abbo records, “The city quakes, its people terrified, and trumpets blare, That all without delay should aid the trembling tower.” Yet, the tower held.

The next day the Vikings used a new tactic. They dug tunnels to weaken the tower’s foundations. But the Parisians discovered them and poured boiling oil, burning the Vikings alive. On the following day the Vikings led yet another frontal charge and this time they created a hole in the tower’s side. But still the Parisians held amidst the ruins of their tower. The Vikings even tried to light a bonfire at the tower’s gate but it only kept them from attacking and the tower held.

After these repeated failures the Vikings took a break. They raided the countryside and gathered the materials they needed to make five massive battering rams, driven by wheels and manned by 30 men. Once ready they sent the rams forward all while firing pots of molten lead into Paris. But the stalwart defenders held, knowing that if they failed the Vikings would show them utterly no mercy. Next, Sigfred ordered trenches built near the stone towers from which his catapults could better fire on the tower. But the trenches inhibited the battering rams, which got caught in the muddy terrain. While Sigfred’s tactics didn’t always work he had an endless supply of them. The warlord’s next plan was to take three ships, fill them with tinder, set them on fire and let them crash into the bridge. But the ships caught on submerged stones, and the Parisians cried thanks to Saint Germanus for the miracle.

The siege continued on into the next year. In March, Count Heinrich of Saxony arrived with his horsemen, the first relief force sent by Emperor Karl. Heinrich and his cavalry harassed the Vikings but could not seriously hurt them. Still, they were a welcome addition to the wearied Parisians defenses. But they were not enough, so Odo and a number of loyal men left the city and travelled to northern Italy where they begged the Emperor for help. Karl assigned Odo a small army and told him he would follow once the rebellions in Italy were done.

By now, the Vikings were sick of the siege. Recognizing the city wouldn’t fall, Sigfred and the bulk of the Vikings abandoned the area, though they did leave behind a smaller force led by Rollo. Odo returned in June and he and his men fought their way to Paris where they joined the defenders. Afterwards, Rollo abandoned any attempt to take the city. Instead, he decided his best course of action was to camp outside Paris and force the Franks to pay them tribute to leave. On 24 October Karl der Grosse arrived with an army. Between the Emperor’s forces and the Parisians the remaining Vikings were certainly outnumbered. But Karl wasn’t there to fight. First, he offered the Vikings 700 pounds of silver to leave; which is understandable if a bit cowardly. For decades Frankish leaders paid off their enemies to preserve the life of their own troops. But shockingly, Karl also gave Rollo and his men permission to sail down into Burgundy! The southeast was then in revolt and the Emperor decided to bleed out his rebellious nobles by sending the Vikings their way. Laid down with cash and the Emperor’s permission to smash in heads, Rollo and his bands sailed south, much to the wonder of the Parisians who had spent 11 months trying to keep the Vikings from doing just that. Politics makes for strange bedfellows to say the least.

While he was there, the Emperor decided to build up his support in Paris. If he hadn’t taken a shine to Odo before, he certainly did now. Odo proved himself as a brave, intelligent leader, whose many connections made him the natural leader of the northern part of West Francia. Karl der Grosse bestowed Odo with his father’s old honores, giving him the county of Orléans and the monastery of Saint Martin of Tours, among others. This made Odo one of the most powerful men in the entire empire. But Karl didn’t stop there. The Emperor understood that the Carolingian dynasty was literally failing. He was still struggling to get his bastard son Bernard legitimized, and the only rightful heir, Charles, son of Adelaide of Paris, was still a child. In these dire straits, Karl may have looked to expand the household and bring in some distant relations. He made a grant for prayers for Odo’s father Robert le Fort, something which was not done for anyone other than royalty. The Emperor probably didn’t plan for Odo to be one of his subordinate kings, but he showed Odo such favor that he was practically King of West Francia in all but name, and even that was soon to change. Meanwhile, Karl adopted Boso of Provence’s son Louis, and recognized him as King of Provence.

Karl der Grosse was not an inspiring figure. He had a reputation for paying off Vikings rather than fighting them. He hadn’t earned his vast realms but only got them through happenstance. Finally, he was beset by ill health in the late 880s. Karl tried to be everything his empire needed, but he wasn’t enough. While Karl tried to hold his vast empire together and put down noble revolts his vassals were the ones acquiring glory and loyalty by defeating the Vikings. In West Francia, Odo was the muse of poets. In the eastern half of the empire, that was Arnulf of Carinthia, illegitimate son of Carloman of Bavaria. In 887 Arnulf revolted against his uncle. Almost immediately, Karl’s support evaporated. As a last-ditch effort to save his throne Karl sent his nephew a piece of the True Cross, which Arnulf had sworn upon when he took his oaths of loyalty. This brought Arnulf to tears as he contemplated his betrayal, but by now it was too late to turn back. He deposed his uncle and confined him to an estate in Alemannia. Within a few short months Karl fell ill and died on 13 January 888.

The Carolingian line continued briefly in the east, but in West Francia there was no one from the house of Charles Martel to take up the throne. However, though there was no chosen successor, everyone knew who the next king would be. Early that year the nobles of northern West Francia assembled and selected Odo as their new king. That February archbishop Walter of Sens crowned him at Compiègne. For the first time in 137 years West Francia had a non-Carolingian king. But Odo wasn’t the only king in the west. Count Ramnulf of Poitiers claimed kingship of Aquitaine, Rodolphe was elected King of Upper Burgundy and Louis of Provence held the south of Burgundy. As the Carolingian House failed the empire cracked into a half dozen kingdoms, all at a time when the great heathen armies came back with all new vigor.


Anthony Adams and A.G. Rigg, “A Verse Translation of Abbo of St. Germain’s ‘Bella Parisiacae urbis’” The Journal of Medieval Latin , 2004, Vol. 14 (2004), pp. 1-68.

Fillipo Donvito, “Besieging an Island City,” Medieval Warfare, Vol. 5 (5) 2015, 29-35.

Matthew Innes and Simon MacLean, The Carolingian World, 2011.

Rachel Stone, Charles West, Charles West, and Simon Maclean, Hincmar of Rheims: Life and Work, 2015.

Simon Maclean, Kingship and Politics in the Late Ninth Century: Charles the Fat and the End of the Carolingian Empire, 2003.

Simon, Maclean, “The Carolingian response to the revolt of Boso, 879-887,” Early medieval Europe, 2001-03, Vol.10 (1), p.21-48