Ragnar Lothbrok didn’t have an easy life, and at one point in Vikings he got very sick, but what he had was never revealed. So, what illness did he have after the Vikings siege of Paris? Created by Michael Hirst, Vikings made its debut on History Channel in 2013 and was originally planned to be a miniseries. However, it was so well received by critics and viewers that it was renewed for a second season, and it’s now received its own spinoff series, set 100 years in the future, called Vikings: Valhalla. While Ragnar Lothbrok isn't in the TV show, his legacy still lives on and the legend of his deeds bear a considerable weight on the series. Vikings initially followed Ragnar Lothbrok (Travis Fimmel) and his travels and raids alongside his Vikings brothers, from the start of the Viking Age – marked by the Lindisfarne raid, as seen in season 1 – onward. The series shifted its focus to Ragnar’s sons and their own journeys, making them the protagonists, though that didn’t make Ragnar’s death any easier.

Ragnar met his fate in season 4 when he was thrown into a pit of snakes, but before that, Ragnar became very ill, making fans question what was wrong with him as the series never revealed what he had. Season 3 saw the Vikings siege of Paris, a confrontation between King Charles the Bold’s Frankish forces and the Viking army led by Ragnar Lothbrok. During the first assault, Ragnar climbed a tower, but was pushed over the edge and suffered a very bad fall, hitting his back, crashing against a wall, and falling on a pile of dead bodies. This fall had consequences, as Ragnar was later seen vomiting, coughing, and peeing blood, though that didn’t really stop him from continuing with his plans, and they attacked Paris a couple more times. Viewers have since speculated as to what Ragnar’s illness was all about, and there have been some pretty good explanations.

Related: Vikings: What Happened To Ragnar Lothbrok's Body After His Death

Ragnar's Illness Remains A Mystery

Ragnar comes back to Kattegat after a 10-year-absence in Vikings

Given Ragnar’s symptoms and how he was able to recover after the Vikings siege of Paris, he most likely had kidney damage. As bad as the hit to his back was, Ragnar didn’t hurt his spine as he was able to walk, so it was an internal injury. As it’s not for sure that Ragnar Lothbrok was a real person, there are no historical records that could point to what Ragnar could have had, so it’s all up for viewers’ interpretation. Symptoms of kidney failure include discomfort in the abdomen, urinating blood, and nausea, and they all fit with what Ragnar went through. It’s also possible he had a lung injury given the coughing, or it might have just been a consequence of the hit to his back.

Vikings Could Never Have Classified A Disease In Modern Terms

Ultimately, the injury (as bad as it was) wasn’t enough to kill or even break Ragnar, but he wasn’t invincible either and couldn’t escape when he was thrown into the pit of snakes. The problem with diagnosing Ragnar's illness comes mainly from the time period itself. At the time, modern medicine consisted of strange and outdated techniques. Couple that with the fact that the knowledge of germs wasn't even around yet, and Ragnar's symptoms have the perfect storm of an unconfirmed illness. Ragnar's death came later, but he surprisingly survived his injuries if he had, in fact, gotten kidney damage from the fall. While medicine was in its infancy during the time of Ragnar's reign, the Vikings were a rather forward-thinking culture, and that included their views on medicine – perhaps it wouldn't have been incurable. Either way, any diagnosis or cure on Vikings wouldn't be anything that modern audiences recognize, as most medical advancements made have only really occurred within the last 200 years.

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