The Real Bjorn Ironside: Ragnar Lodbrok’s Most Famous Son

Thanks to the History Channel’s TV Show Vikings, Bjorn Ironside might be the most famous son of the legendary raider Ragnar Lodbrok. But the character we meet on the show is only loosely inspired by the Bjorn described in the sagas of Ragnar and his sons. Moreover, the legendary warrior we meet in the sagas, written 400 years after he lived, may have taken dramatic liberties when describing the life and exploits of the real 9th-century Viking king and warrior. This article covers what we know about Bjorn Ironside, from his parentage to his escapades around the Mediterranean.

Most of what we know about the supposed life of Bjorn Ironside comes from the 13th-century sagas about the lives of Ragnar Lodbrok and his sons, written around 400 years after the characters they immortalized were supposed to have lived. Many episodes in these stories seem unbelievable, such as Ragnar slaying a dragon, which casts doubt on the historicity of the sagas.

Nevertheless, the legendary Bjorn Ironside seems to have been based on a real Viking warrior who lived and raided in the 9th century. This son of Ragnar is mentioned in several contemporary French sources including the Annlaes Bertiniani, Frankish records kept by several monks in the 9th century, and the Chronicon Fontanallese, compiled at the French Abbey of Saint-Wandrille in the 840-850s.

So, while many of the details that we have about the life of Bjorn may be questionable, the legendary figure does seem to be based on a real person.

Son of Ragnar Lodbrok

Bjorn is described as the son of Ragnar Lodbrok, a legendary king of Denmark and parts of Sweden. He seems to have been considered a “historical celebrity” in the age of Snorri Sturluson, an Icelandic Christian who wrote about Norse mythology and Viking history in the 13th century. He notes that the famous Skaldic poet Bragi Boddason composed many works about the deeds of Ragnar.

In addition to being a famous warrior, Ragnar had many wives and children, which may have been common for the Viking elite in the 9th century. He first won the hand of Thora, the daughter of the Jarl of Gotland, by defeating a dragon that was terrorizing the region. They had two sons, Eirik and Agnar.

He met his next wife while raiding the Norwegian coast; the Vikings raided one another as well as across Christendom. He met and fell in love with a young woman named Kraka, but according to one source, he was not going to marry her because she was a pauper. Instead, he was in negotiations to marry the daughter of Eysteinn Beli, an ally of Ragnar who was the king of other parts of Sweden. But Kraka conveniently revealed that this was a fake identity, and she was Aslaug, the daughter of the hero Sigurd and the Valkyrie Brynhild. The pair married and had five sons: Ivar the Boneless, Bjorn Ironside, Hvitserk, Rognvald, and Sigurd Snake-in-the-Eye.

According to the Gesta Danomorum, a 12th-century Danish history written in Latin by Saxo Grammaticus, Ragnar had several other sons. He had a son Fridleif and two daughters with the shieldmaiden Lagertha, though they seem to have lived with their mother. Ragnar also had a son, Ubbe, with an unknown woman. He appears in one story trying to usurp his father’s position. Ragnar may have had other children, especially daughters, whose names have not survived through history.

It is worth noting that this is one of the key differences between the Bjorn Ironside of the sagas and the Bjorn we meet on the History Channel’s Vikings. There, Bjorn is described as Ragnar’s oldest son, with his first wife Lagertha, and has an antagonistic relationship with Ivar, Ragnar’s youngest son by Aslaug. This creates an alternative family dynamic and drama to what we see in the sagas.

Bjorn is well known for his raiding activities, which seem to have taken him as far as the Mediterranean. But he may have had little choice in his career path. Some French sources suggest that the Danes had the practice of sending younger sons away to make their fortunes independently, diminishing conflict for succession with older sons. Whether this is a real Viking tradition, or one imagined by outsiders looking in, this does seem to be what happened.

While Eirik and Agnar stayed in Denmark, Ivar, Bjorn, and his brothers reportedly set themselves up as a raiding party on Zeeland, from where they raided surrounding Viking territories including Jutland, Gotland, Oland, and other minor islands. They were led by Ivar, who was the oldest and described as the most cunning and strategically intelligent. It is unclear why he was called “the Boneless,” it could be a reference to a medical condition or a cultural reference that has been lost. Bjorn is described as an enforcer and so ferocious that he could singlehandedly turn the tide of a battle. This is probably why he was called jarnsida, which means “iron arm” or “Ironside.”

While Ragnar was raiding in the Baltics, where the Vikings may have been active from as early as the 7th century, and his sons with Aslaug were raiding closer to home, Eirik and Agnar became embroiled in diplomatic issues with Eysteinn Beli. There are several different accounts of what caused the conflict. One source suggests it was resentment over Ragnar snubbing the earlier marriage proposal, another that Ivar and Bjorn’s raids were putting pressure on Eysteinn’s territory, and yet another that Eirik and Agnar were just greedy and wanted to claim his territory. Whatever the cause, Eirik and Agnar were captured and killed. The band of brothers on Zeeland then successfully avenged them.

Here, the sagas about Ragnar suggest that Ragnar was displeased because his sons were starting to rival his fame. This seems unlikely since we also know that Ragnar later left Ivar in control of Denmark while he was off raiding, and made Bjorn king of Sweden, possibly not long after these events. This makes it appear that following the deaths of his sons with Thora, Ragnar started to establish his sons with Aslaug as his new heirs. These do not seem like the actions of a jealous and disgruntled father.

There are many other stories of Bjorn’s raiding exploits, and it is unclear where they fit into Bjorn’s timeline, such as whether they pre- or post-date the deaths of Eirik and Agnar. Suffice it to say that Bjorn Ironside raided widely across Europe and made a name for himself as a terror.

As mentioned above, the earliest contemporary historical references to Bjorn, called Berno, come from the French annals. They placed him in West Francia in 855. There he is said to have engaged in small raids before teaming up with another Viking leader, Sigtyrgg, to sail up the Seine and assault the territory of Charles the Bald.

They were beaten by Charles at Champagne, but the victory was not decisive. While Sigtyrigg left, Bjorn summoned reinforcements and established a winter camp in the region, which he called Givold’s Grave, from where he raided Paris in 856 and 857. He then built a fortification on the island of Oissel, near Rouen, and used it as a base to raid the surrounding territory. Charles the Bald unsuccessfully tried to besiege the fort in 858.

That is the last we hear of Bjorn Ironside in France, but the Vikings continued to be present. They plundered Paris again in 861 and fought as mercenaries for various French rulers. But by this time. Bjorn himself may have moved on.

Vikings in Spain and Portugal

While we know a lot about the Vikings in England and France, it is less well-known that they also raided across the Iberian Peninsula between the 9th and 11th centuries. This is largely because their activities coincided with the rise of Muslim rule, which had a much bigger impact on the formation of the region. But Vikings in the region are mentioned as Normanni or “Norsemen” in the Latin sources and majus or “heathens” in Islamic sources.

The first major raids predate Bjorn, starting in 844 when the Vikings sailed a fleet with red sails into Galicia and started plundering villages until they were stopped by King Ramilo I of Asturias. He later fortified the coast against further Viking raids.

Nevertheless, the Vikings would go on to assault Lisbon, which was a Muslim Emirate. From there they reportedly sailed south with a fleet of 100 ships and 4,000 men to raid the cities of Sidonia, Cadiz, and Sanlucar. They eventually sailed upriver via the Guadalquivir, exterminating the village of Coria del Rio and then sacking Seville. These particular Vikings were eventually driven off.

When Bjorn arrived in the area with Hastein, who seems to have been his guardian suggesting that Bjorn was still a young man, the locals were more prepared. According to the Albeldense Chronicle, they arrived in 858 with a larger fleet than had previously been seen. Passing the heavily fortified coastal towns, they sailed up the Arosa estuary and laid siege to Santiago de Compostela. The siege was broken when Count Pedro Theon showed up with reinforcements and destroyed about a third of Bjorn’s fleet. They were forced to sail back down the Guadalquivir, where they were prevented from disembarking. Instead, they continued raiding coastal towns from Algeciras to Orihuela, as well as locations in Morocco and the Balearic Islands.

Having made it to the Mediterranean, Bjorn decided to continue to Italy, reportedly hearing of the riches of Rome. One source suggests that Hastein had the idea to make Bjorn the new Holy Roman Emperor.

Upon landing in Italy, they immediately sacked Pisa before starting their journey towards Rome. According to the story, en route, they stopped at Luni, which they mistakenly thought was Rome due to the city’s wealth and defenses. Bjorn and Hastein reportedly thought that a siege would take too long and decided to use trickery to get themselves behind the walls.

The Vikings sent a message to the Bishop of Luni saying that their leader Bjorn was either dying or dead, and that at the last minute, he had converted to Christianity. He wanted to be buried on sacred ground. The bishop was taken in and let a small group of Vikings into the city to complete the burial. Upon passing the city gates, Bjorn jumped up, either from his sick bed or his coffin, and held the gates to let the Vikings enter the city.

Taking what they wanted from Luni, Bjorn decided that if this was just a small Roman city, Rome itself would be too heavily fortified to make it a viable target. Therefore, they turned around and headed home, plundering their way through Tuscany, Sicily, and North Africa along the way. They may also have found themselves in a face-off with a Byzantine fleet wielding Greek fire. By 862, they were reportedly back in the north of France, with just 20 of their original ships.

It was not long after this that Ragnar found himself reunited with his brothers following the death of his father at the hands of King Aella of Northumbria, who reportedly threw him in a snake pit.

Seeking vengeance, the brother descended on England in 866 with 400 ships. They set themselves up in York, where Ivar the Boneless had created a stronghold and found allies. Together they led a “Great Heathen Army” that devastated England and destroyed the forces of King Aella. They tortured Aella to death. According to the stories, they carved an eagle into his back and then salted the wound. After this, they extracted his ribs with a sword in such a way that it also pulled out his lungs, eventually killing him.

While Ivar seems to have stuck around in England to carve out new territory for himself, Bjorn seems to have returned to Sweden where he was king, at least of the part around Uppsala.

We don’t have any information about Bjorn’s later life or how he died. He may have died peacefully since he was succeeded by his son Eirik, who was in turn succeeded by the son of Bjorn’s other son, Refil. Bjorn is credited with founding a dynasty that ruled in Sweden from the 860s until 1060, called the House of Munso. The dynasty is named after a barrow found on the island of Munso in the 18th century which antiquarians once claimed belonged to Bjorn.