Authenticity
There has been debate as to the authenticity of such accounts. Some credit the Gotland picture stones as archaeological evidence attesting to the authenticity of the blood eagle as presented in Norse literary traditions. Some have suggested that the blood eagle was never actually practiced, arguing that such accounts are based upon unsupported folklore or upon inaccurate translations. Ronald Hutton's The Pagan Religions of the Ancient British Isles: Their Nature and Legacy reports (p. 282) that "the hitherto notorious rite of the 'Blood Eagle,' the killing of a defeated warrior by pulling up his ribs and lungs through his back, has been shown to be almost certainly a Christian myth resulting from the misunderstanding of some older verse." However, it has also been suggested that an Old Norse word for "blood eagle", blóthorn or blóðörn, indicates some type of ritual existed. Alfred Smyth (1977) is a particularly enthusiastic supporter, taking the blood-eagle rite as a historical practice of human sacrifice to the Norse god Odin.
Roberta Frank writes in her article "Viking Atrocity and Skaldic Verse: The Rite of the Blood-Eagle": "By the beginning of the nineteenth century, the various saga motifs—eagle sketch, rib division, lung surgery, and 'saline stimulant'—were combined in inventive sequences designed for maximum horror." She concludes that, reveling in the misdeeds of their pagan predecessors, the saga authors took skaldic poetry originally intended to make elliptical reference to defeat in battle (causing one's back to be scored by eagles, i.e. killing them and thus turning them into carrion) along with separate martyrdom tracts expressing the final tortures of worthy victims in terms reflective of the intended execution of Saint Sebastian (shot so full of arrows that their ribs and internal organs were exposed) and combined and elaborated them into a grandiose torture and death ritual that never was.
If the procedure were performed, the condemned would die of suffocation very soon after the lungs were pulled out (since breathing occurs via the diaphragm and chest muscles) and would probably lose consciousness due to blood loss and shock before that.
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