Historically and in the 2013 television series, Vikings, Ragnar Lothbrok fathered many children. At the start of the series, Ragnar (Travis Fimmel) is a farmer with dreams of traveling West to discover new lands to raid. He is married to Lagertha (Katheryn Winnick) and the two have two children together: Bjorn and Gyda. After a great deal of resistance, Ragnar decides to sail West, where he and a small group of Vikings raid Northumbria. This raid would launch Ragnar into a new realm of fame that would include becoming Earl of Kattegat and eventually, King of Denmark.

Ragnar's achievements would gain a massive amount of recognition, including that of Princess Aslaug's (Alyssa Sutherland). The two would begin an affair that would blow up in Ragnar's face once she fell pregnant and decided to travel to Kattegat. Aslaug's arrival would cause a rift between Lagertha and Ragnar, which would result in Lagertha leaving Kattegat and taking Bjorn with her. Together, Ragnar and Aslaug would have four children: Ubbe, Hvitserk, Sigurd, and Ivar.

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Given Ragnar's prestigious reputation amongst the Vikings, his sons are guaranteed to experience a fair share of admiration and jealousy throughout their lives. Some of Ragnar's children were given epithets that only elevated their status amongst the Vikings. Bjorn (Alexander Ludwig) was given the nickname "Ironside" as an ode to his iron skin. Many believed that given Bjorn's apparent indestructibility, that he was protected by the Gods. Shortly after his birth, Sigurd (David Linström) would be called "Sigurd Snake-in-the-Eye" by his mother because of his eye that resembled a snake's. Ivar (Alex Høgh Andersen) would also receive an epithet. He would be hailed "Ivar the Boneless" because of his disability that left his legs useless. Even though all of Ragnar's sons didn't receive epithets, they do all have traits that could make them the worst to confront on the battlefield.

Hvitserk, Bjorn, Ivar, Ragnar, Ubbe, and Sigurd

One quality that all the Ragnarssons share is that they are all skilled warriors. Only Bjorn, Ubbe (Jordan Patrick Smith), and Hvitserk (Marco Ilsø) were given the chance to train and learn from Ragnar before he vanished after their defeat in Paris. Instead of learning from Ragnar, Sigurd and Ivar were left to learn from their older brothers and the various other Viking warriors in Kattegat. No matter where they learned their skills, all of Ragnar's children were daunting forces on the battlefield. However, it is only in their differences that the most dangerous son of Ragnar can be identified.

As the oldest son of Ragnar and the only surviving child of Ragnar and the famous shield-maiden Lagertha, Bjorn already has the makings of a great warrior. Both of his parents are well-known for their actions during battle, and their leadership outside it. Like his father, Bjorn becomes an accomplished raider and explorer, who the people of Kattegat eventually begin to trust more than Ragnar. Bjorn's exploits begin to accumulate more fame than his father and his reputation nearly grants him the honor of being the first King of Norway. It is in death that Bjorn proves himself to be worthy of his Ironside epithet. After being stabbed by Ivar, Bjorn miraculously manages to ride onto the battlefield and his body takes several arrows. The ghostly sight ultimately frightens so many within Ivar's army that they flee.

Bjorn Ironside death scene

In the midst of the series, Ragnar tells Bjorn that "Power is only given to those who are prepared to lower themselves to pick it up." While Bjorn shared Ragnar's ambition and his attitude toward ruling, neither of them ever wanted to be king. The burden of ruling was something that fell into their laps and caused them both a great deal of unhappiness. Arguably, Ubbe had a better head on his shoulders for ruling. This is best exemplified in he and Bjorn's stay in England, where Ubbe agrees to convert to Christianity to gain the land King Alfred has promised them. Aside from being an accomplished warrior, Ubbe is also incredibly responsible. Ubbe weighs the risks of each situation and unlike many others in his family, he is not above compromise. However, the fault in this is that Ubbe can sometimes find himself being too trusting.

Like his eldest brothers, Ivar shares some of Ragnar's most compelling qualities. Ivar shares Ragnar's intellect both on and off of the battlefield. After being ridiculed because of his disability his entire life, Ivar channels his frustration into action. Ragnar tells Ivar, "Everyone will always underestimate you. You must make them pay for it," and Ivar does. Despite his disability that led many to render Ivar useless, he never backs down from a fight. In battle, he rides on a chariot and when that doesn't work, he uses his axes to cut down his enemies.

Ivar the Boneless

Off the battlefield, Ivar leads out of fear as opposed to respect. Shortly after he and his brothers have used the Great Heathen Army to exact revenge against King Aelle and King Ecbert, Ivar accidentally kills his brother Sigurd by flinging an ax into his abdomen. He later takes control of the Great Heathen Army and stages attacks across England. Ivar becomes the King of Kattegat where his power begins to make him feel untouchable, which makes him more dangerous. After his child was born with a physical detriment, unlike his father, Ivar does leave his child for dead. When he discovers his wife has betrayed him, he strangles her and leaves her body next to the bones of their son.

Ragnar has many children who all inherit pieces of his famous persona. How they utilize the skills of both Ragnar and their mothers is what makes them such unique characters despite coming from the same circumstances. Of all the Ragnarssons, Ivar the Boneless is easily the most dangerous. As strategic as he can be on and off the battlefield, his anger and violent rage have proven to blind him to reason at times. The final scene Ivar shares with Ragnar is credited as the true birth of Ivar the Boneless. Ragnar's final words to his youngest son are "Be ruthless," and those that know Ivar, know that he takes those words to heart to become the most formidable Ragnarsson.

Vikings is now streaming on Peacock.

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