**Painting by Édouard Jolin, can be seen in the cathedral of Nantes. Depicts the murdering of bishop St Gohard by the Vikings in 843.
The Vikings loved France. They loved it not because they wanted live there, but because it was full of undefended monasteries and churches filled with valuable treasure. Charlemagne’s Empire was the favored realm of Christendom, and under it the church prospered—and they made themselves rich. Unfortunately for the Vikings, Charlemagne was a keen tactician and an astute politician. His grip on his empire was firm as steel, making the river systems therein nearly impenetrable. Not until his death did the empire he so carefully sewed begin to unravel. His only son, Louis, while not an entirely incompetent ruler, oversaw the partition of the empire that allowed the Vikings to attack.
Charlemagne was lucky. The Franks had not yet adopted the tradition of primogeniture, the passing of a ruler’s lands to the eldest son, which should have forced him to split his empire up among his sons. Louis was Charlemagne’s only legitimate heir (there were, of course, many illegitimate children), making the preparations for his succession quite simple. Louis, however, had already fathered several sons by the time his father died, and he quickly set about making preparations to secure his succession upon his own eventual death.
All was well until Louis fathered a fourth son with his second wife. Per the custom, he began preparations to add his latest heir to his inheritance, an act that incited his other three sons to rebel against him. Thus began the first civil war in the Frankish Empire. Troops were called away from their posts across the land to help fight on one side or the other. The empire’s economy collapsed. For a time, the entire continent seemed to be at war.
In 841 A.D., years of fighting between the factions culminated at the battle of Fontenoy-en-puisane from which emerged the Treaty of Verdun. The treaty effectively split the empire among Louis’ three living sons (alas, poor Pepin died during the fighting). In the West, Charles the Bald inherited a territory roughly corresponding to modern France. His brother Lothaire inherited lands in Italy, and a thin strip all the way to the Baltic via modern day Switzerland and Germany. In the East, Louis the German inherited lands from modern day Germany to modern day Poland. This partition would affect the geo-political makeup of Europe until today.
Following the partition of the empire, the smaller kingdoms therein remained in constant conflict. Until this time, no major outside threat seemed to loom over the Franks, so they continued to ignore the signs that, in retrospect, were a little too obvious. The Vikings had been raiding coastal communities intermittently for decades, but the leadership of the Franks appear to have not acknowledged their increasing boldness. After all, Charlemagne’s defenses had proven an effective deterrent to upriver excursions in the past. What the Franks did not know is that the Vikings had aggressively pushed into the British Isles, including the heavy colonization of Ireland, keeping most of them busy elsewhere. It took only one attack to set into motion a century of invasions in France, invasions which triggered the demise of the Carolingian dynasty.
In 843 A.D. hostilities between the Frankish factions finally ceased. The Empire, now a conglomeration of smaller kingdoms, experienced a brief period of peace. On June 24th, however, it all proverbially went to hell in a hand-basket. In the city of Nantes, nestled along the Loire River in the southern part of the region of Brittany, the festival of Saint John (La Saint Jean, in French) kicked off with the usual festivities: a local fair where merchants and pilgrims gathered to exchange goods and services prior to attending mass in the city’s romanesque cathedral. Seeing as it was a religious holiday, no one ever imagined anything terrible would happen, and so they neglected to post guards at the entrances to the city, and they had left those entrances open. Among the visitors to the city were a great number of hooded men—tradesmen, so the denizens of the city thought. But these men had not arrived at the city to trade. They were scouts. Their mission was to infiltrate the city, perhaps simply to see how easy it might be. Seeing that the city was completely undefended, they revealed themselves as weapon-clad warriors with more malicious intents than to celebrate a Christian saint.
The entire account of this history was recorded in a document called the Annales D’Angoulême, which did not survive to today. It is, however, incorporated into an account written at the end of the 11th century called the Chronique de Nantes (the Nantes Chronicle). Nantes at the time was a well known religious and economic center, a truly rich target for any foreign invader. Its bishop, Gohard, was well known and respected among his peers. The attack itself is a brief passage in the chronicle, and all we may really gleam from it is that the bishop was égorgé, meaning he had his throat slit in front of his audience. News of the sack of Nantes quickly spread across Christendom and is a referenced event in several other chronicles of the time, such as the Annales Bertonni, the works of Adam of Bremen, and several other more obscure writings. At the time, the event was a veritable shock to the Carolingians.
The most important aspect of the attack is that it was the first of its kind. Never before had the Vikings sacked a major settlement in the Carolingian Empire. The attackers, referred to in the Annales D’Angouleme as Vestfaldingi, men from Vestfold, were also not who one might have expected to make such a daring incursion. The fact that the chronicle names the specific kind of Vikings who sacked the city tells us two things: that they were Norwegians, not Danes, and that they had taken the time to introduce themselves to their victims.
We know from numerous other sources that the Danes and the Norwegians had a certain rivalry between them during the Viking Age. While the Danes were far more involved in England than the Norwegians, the Norwegians competed rather effectively with their Danish rivals for lands in Ireland. It is therefore not surprising, although still mostly an educated guess, that the Vikings who sacked Nantes had travelled there from Ireland. Furthermore, it is fairly certain that they boasted of their victory and, according to oral tradition, news of their success would have travelled quite fast indeed across the Viking world.
It was only two years later that the Danes entered the Seine river and sacked Paris. To have done so a few decades earlier would have been suicide. The leaders of the Danes took a major risk by leading as large a fleet as they did up to the walls of Paris. But they already knew the Franks were weaker than before. They knew because of Nantes.