There’s an infamous legend that Vikings carried out a beautifully brutal torture ritual said to have involved spreading a person’s ribs from their spine to symbolize an eagle’s wings and hanging their lungs out through the wounds while they are still alive.

The ritual has been featured in the TV show Vikings and the recent Assassin’s Creed: Valhalla video game, but did it really happen? Or is it just the stuff of tall tales and misinterpretation? Researchers from Keele University and the University of Iceland recently investigated this grisly ritual and concluded that this unpleasant death is anatomically possible. Furthermore, a sociocultural analysis of Viking culture indicates that this type of ritual would not necessarily be out of the ordinary. 

Their findings were recently reported in the historical journal Speculum. 

We know about the so-called “Blood Eagle” torture method thanks to descriptions in early-Medieval poetry written in Old Norse and Latin. One Icelandic source from the 12th century reads: “He carved an eagle on his back in such a way, that he put a sword into the chest cavity at the spine, and cut down along all the ribs to the loins, and pulled out the lungs through the cut. That was the death of Hálfdan.” Another text from 12th-century Denmark speaks of a torture ritual that involved putting the “likeness of an eagle” onto a victim’s back.

However, no definitive archeological evidence of the ritual has ever been discovered, leaving scholars to wonder whether the legend of the “Blood Eagle” was simply a misinterpretation. While this latest research can not definitely prove whether the ritual actually did occur, it certainly seems plausible. 

“We started off by reanalyzing the medieval descriptions of the ritual – really going through them with a fine-tooth comb,” Dr Luke John Murphy, study author from the Department of Archaeology at the University of Iceland, told IFLScience.

“Then we went over the two sets of constraints any blood eagle would have had to have taken place within: the limits of the human body, and the limits of human behavior. Basically ‘can this be done physically?’ and ‘can this be done socially?’” 

An analysis of sources from the time clearly showed the Viking culture was not shy about gruesome displays of death: mutilation, brutal beheadings, and the displaying of dead bodies in religious settings were not out of the ordinary. Using cutting-edge computer software, they also showed that the ritual is anatomically possible. Although, rest assured, it would not have been a pleasant experience.

"Anatomically speaking, you would be surprised at how much skin can be cut and removed without a significant amount of blood loss," added Dr Monte A Gates, study author from the School of Medicine at Keele University.

"The back is quite big and there are many blood vessels to supply blood to that skin. But these blood vessels aren't terribly big and the first stage of any blood-eagle – getting rid of the skin on the back – wouldn't necessarily kill a person from blood loss. Dying from shock, is a different matter," noted Gates.   

"However, the next phase of the blood-eagle – starting to cut the ribs along the back and opening the thorax – would've certainly killed the person almost immediately.  This is because, even if you missed the heart and lungs, the main artery serving the entire body runs along the side of the spine where ribs would've been cut. Cutting into this artery – the "thoracic aorta" –  would cause blood pressure throughout the body to immediately plummet, including the brain," he continued.

"An analogy would be like turning on a gardening hose, and then cutting it in the middle," he added.