One of the cornerstones of Norse mythology is Ragnarök. “Ragnarök” means “twilight of the gods” and it is a prophecy originally delivered to Odin about how the world will end. You can read our full account of what happens at Ragnarök, according to the prophecy, here.
But it is always complicated when talking about Ragnarök since it is sometimes unclear whether it has already happened. It seems clear that the pagan Vikings probably thought it hadn’t happened yet.
One of the key elements of the Ragnarök prophecy is that Odin chooses the bravest fallen warriors to spend their afterlife in his hall Valhalla in Asgard.
There they feast and train to join the gods in the final battle of Ragnarök. But according to the prophecy, they will lose the battle, and Odin will be devoured by the mighty wolf Fenrir.
If Ragnarök has already happened, Odin can’t be taking warrior souls to Valhalla.
But our accounts of the Ragnarök prophecy all come from text written down after the Vikings converted to Christianity, most notably by the 13th-century Icelandic Christian historian and poet Snorri Sturluson.
It is entirely possible that he and others like him thought that Ragnarök had already happened, making way for a new Christian era.
This is implied by texts in which the Norse gods are presented as ancient Viking kings, suggesting they belong in the past.
But is there any firm evidence to support the claim that Ragnarök has already happened ?
Scientists think they may have found some.
Three Winters Without Summer
According to the Ragnarök prophecy, the twilight of the gods will be heralded by a series of omens and pre-apocalyptic events.
Key among these events is three year-long winters uninterrupted by summer, known as “Fimbulvetr” or “mighty winter.”
This causes major famine that leads to war, with brother killing brother and father killing son.
It also makes the mighty serpent Jormungandr uncomfortable in the waters where he lives surrounding Midgard, so he emerges.
The serpent is so enormous that he is part of the natural ecosystem, and his movement causes earthquakes and tidal waves.
These are some of the disruptions that cause the world to shake and allow other monsters, including Fenrir, Loki, and Surtr, to break out of their prisons and lead the charge against the gods.
Some scholars believe that the Fimbulvetr may have happened in 536 CE, shortly before the Norsemen became “Vikings,” which they became when they started raiding surrounding territories for resources.
This is because the year 536 CE may have been “the worst year in history,” due to three major volcanic eruptions that caused a long volcanic winter.
Volcanic Winter
A volcanic winter is believed to have started across the Northern Hemisphere in the year 536, considered to be the worst that the hemisphere had experienced in 2,000 years.
It is believed to have been caused by at least three more-or-less simultaneous volcanic eruptions, although exactly which volcanoes erupted is debated.
Evidence that this caused an extended period of low temperatures is found through dendrochronology, which is tree-ring analysis.
This show unusually low growth in a variety of trees between 534-542 CE, which is often evidence of cold winters.
Polar ice cores also show a cryptotephra layer, which is a layer of volcanic ash from a single eruption, dated to the same year, 536 CE.
It is the geochemical analysis of this layer that suggests that at least three different volcanic eruptions, with unique ash signatures, contributed to this event.
While it is uncertain which volcanoes erupted, the most likely candidates are the Mono Craters in northeast California, the Aleutian Arc, a series of volcanic islands at the tip of Alaska, and the Northern Cordilleran volcanic province in the Pacific Northwest region of North America.
Impact on Humanity
Because the Vikings weren’t creating written records at this time, we don’t know how the resulting years, or potentially decade, of colder weather affected them.
But people in other parts of the Northern Hemisphere were also affected and have left accounts.
The Eastern Roman Empire records the event, which coincided with a war with the Vandals, Germanic peoples who occupied what is now Poland, in 536 CE.
The historian Procopius says that the war was accompanied by dread portents including that the sun gave forth light without brightness that almost seemed like an eclipse.
The Roman statesman Cassiodorus made similar observations suggesting that the sun’s rays were weak that year and had a bluish color, that even at noon no shadows were visible, and that the moon remained in shadow even during the full phase.
He said that the winter had no storms and summer had no heat, that there was prolonged frost and unseasonable drought, and that the harvest season was so cold that apples hardened into sour grapes.
The Irish Annals, including both the Annals of Ulster and the Annals of Inisfallen, both report a bread shortage in 536 CE.
The Welsh chronicle the Annales Cambriae suggests that following the Battle of Camlann, in 537 CE during which Arthur reportedly fell, many died across Britain and Ireland, presumably due to famine.
In distant China, the Annals of the Tang Dynasty mention a great cold and famine in 536 CE, and a “History of the South” describes yellowish ash in the sky.
What Happened in Scandinavia ?
While this was happening in other parts of the world, what was likely to be happening in Scandinavia? Scientists now believe that surface temperatures cooled by around 3 ∘C, but around 6.9 ∘C during the growing season.
There was also a significant reduction in rainfall during the growing season, reducing by 15-20mm per month. Archaeological excavations also show the farms were abandoned.
Put together, this suggests that there were significant crop failures.
There is also evidence that the population may have significantly declined, by as much as 50%.
What did this mean for the Norsemen living in Scandinavia at the time ?
Archaeology suggests that the area was sparsely populated, due to the population decline and harsh conditions.
However, there is also evidence of many fortifications, but no external invaders at this time.
This suggests that there may have been infighting among the Vikings, not dissimilar from the Ragnarök prophecy which suggests that brother fought brother.
This may have contributed to the growth of a warrior elite class, which would eventually enable them to form raiding parties to start the Viking Age proper.
Competition for more limited resources would also have contributed to the development of a warrior ethic across society, eventually leading to the Viking Age.
Viking raids probably did not start that long after this crisis, as there is evidence of raiding activity in Estonia from as early as the 7th century.
The Fimbulvetr of 536 CE
It is plausible to say that the Norsemen experienced a kind of Fimbulvetr starting around 536 CE, and that the extreme cold temperatures made life in a region of the world that is already challenging extremely difficult.
This experience may have inspired the stories of the Fimbulwinter before Ragnarök, though the continued worship of Odin by the Norsemen suggests that it was not one and the same.
They probably imagined that an even worse Fimbulvetr would herald Ragnarök.
But while 536 CE might not mark this event, it does seem to have marked a change in Norse culture.
They moved from a relatively peaceful farming culture to one of scarcity, where groups had to defend their resources against neighboring groups.
This led to the need for a warrior class to defend and conquer.
This in turn created the social structure and resources for the Norsemen to start looking beyond their own territories for resources, eventually leading to the practice of raiding and the Viking Age.
