Coming to power with the aid of his brothers, he would co-rule Denmark with Harald Klak before seizing the throne for himself. His long reign featured increasing raiding in the Frankish lands, which would ultimately lead to his downfall.

Scion of the scourge of Charlemagne

It should be no surprise that a King who ruled a medieval kingdom for more than 40 years came from legendary stock. Horik I was born sometime in the late 8th century CE, the son of King Gudred of Denmark. Gudred had found fame and fortune by successfully raiding, from his Danish realm, into the Carolingian Empire led by perhaps the most impressive man of the early medieval age, Charlemagne.

What little we know of Horik and his father is from a Swiss Benedictine Monk, Notker of Saint Gall. He wrote a biography of Gudred in which the scourge of Charlemagne met his downfall in 810 CE, assassinated by either a servant or, even more dramatic, one of his five sons – though not Horik. The crown passed not to any of his sons but to an older nephew of Gudred, who reigned only briefly until 812 CE. The crown then passed to another dynastic part of the family, with Harald Klak and Ragnfred ruling jointly whilst Horik and his four other brothers sought refuge in Sweden during their rule.

Civil wars, brotherly rule, and power sharing

The five brothers decided to attack the joint kings whilst they were away on campaign in western Norway, the furthest part of the realm. Gaining support from Swedish nobles, the brothers defeated the joint kings with the loss of one brother and then set about dividing and ruling the Danish kingdom. Harald, however, managed to escape to the Frankish realms and bide his time to retake the throne seized from him.

In May 815 CE, a huge force of Frankish subjects, mainly Saxons, crossed the River Elbe and marched into the Danish kingdom. Little was achieved, though, as the four brothers gathered a huge armada of over 200 ships to stop this invasion. The raiding from the Frankish realms, the obvious machinations of Harald, would eventually come to a halt by order of the new Frankish emperor, Louis the Pious, in 817 CE.

A dramatic twist occurred in 819 CE when Horik betrayed his brothers and asked Harald Klak to share the Danish throne with him. This may have been done to ensure peace with the larger Carolingian Empire. However, after four years, the partnership broke down, and Harald fled across the border and into the Frankish realms before being finally expelled, permanently, from the Danish kingdom in 827 CE.

In 845 CE, a Viking raid, led by Ragnar, sailed up the River Seine to sack Paris. Photo: The Viking Herald

Sole rule and flirtation with Christianity

Horik would eventually reign in his own right, from approximately 828 CE onwards, after years of repealing raids from the Carolingian Empire. When he had established his sole rule, Horik made diplomatic overtures to Ansgar, the important Archbishop of Bremen. Ansgar wanted to convert the Danish and Swedish realms to Christianity and persuaded Horik to build a church at Hedeby. Horik also helped Angsar to prepare a mission to the Swedish areas of his kingdom. However, Ansgar was largely unsuccessful, and it would take more than two centuries before all of Scandinavia would be converted to Christianity.

Throughout the 830s CE, however, Horik's grip on power seemed to be slipping. There was a series of Viking raids in Frisia, which appear to have not had the backing of Horik. He even sent a personal envoy to Emperor Louis to declare that he had not sanctioned them.

Yet the breaking up of the Frankish kingdom in 843 CE presented an opportunity for Horik to reassert his power and rule. In 845 CE, a Viking raid, led by Ragnar (believed to be Ragnar Lothbrok, a legendary figure, and ally of Horik), sailed up the River Seine to sack Paris. The Frankish King, Charles the Bald, was forced to flee and would eventually pay a ransom of 7.000 pounds of silver to the Vikings. Horik sanctioned further raids on Hamburg and in Frisia.

Downfall and death

It appears though that this increased raiding would ultimately lead to his downfall. Though Horik grew rich from the plunders, these raids seemed to weaken his authority as the various Viking leaders who led the raids grew in wealth, power, and authority. 

One of these Viking leaders was his nephew, Guttrom, who had been exiled. He would return and claim the kingdom in 854 CE. A huge battle was fought where Horik I was killed along with his nephew. The throne passed to Horik's grandson though the power of the Sigfredian dynasty was ultimately shattered. It would reign for about half a century more before Gorm the Old would establish a new dynasty in the early 10th century.

Horik I is largely overlooked in medieval history, somewhat unfairly for a man that managed to rule large Viking realms for more than 40 years. He is nowadays best remembered as a character in two seasons of the popular television series Vikings.

Heading to Denmark soon? Then be sure to visit the Kongernes Jelling – Home of the Viking Kings. More information on this hugely important historical UNESCO-listed monument, where Denmark was "born and created" during the Viking Age, can be found here. 

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