Centuries before Christopher Columbus’ pioneer journey, the Vikings had already reached the Americas, landing in what is now Canada. New study used ingenious dating techniques to pinpoint the timing of the existence of Scandinavian colonization in the Americas: exactly one thousand years ago, in 1021 AD
The conclusion, which has just been released in article in the scientific journal Nature, was made possible through the analysis of wooden artefacts from the L’Anse aux Meadows archaeological site, in the region of Newfoundland and Labrador (far eastern Canada). The study was led by Michael Dee of the University of Groningen in the Netherlands, who worked with colleagues from institutions in Canada and Germany.
Very little is known about the adventure of Scandinavian sailors in the New World. The voyages in the grounds of this side of the Atlantic are evoked in the sagas (stories mixing history and legend) written in Iceland in the last centuries of the Middle Ages.
Viking groups are said to have arrived in Canada from Greenland, where they had succeeded in establishing settlements that lasted for centuries (they were not abandoned until around AD 1400). Icelandic sagas speak of the abundance of timber in the newly discovered lands and evoke conflicts with indigenous peoples, whom the Scandinavians called “skraelingjar”, possibly meaning “people who dress in animal skins”.
Excavations at L’Anse aux Meadows in the 1960s showed that the accounts were correct and that the area likely served as a base for expeditions to other parts of the Atlantic coast. The dates obtained at the archaeological site, however, were a mess, covering virtually everything known as the Viking Age (ranging from AD 793 to AD 1066, depending on the convention adopted today).
This was probably due to the technological limitations of dating methods at the time of the original excavations, with no controls able to take into account material contamination and other factors.
This is where the new research comes in, coordinated by Michael Dee. As in the 1960s, researchers used the carbon-14 method, an unstable form of the chemical element carbon found in living things.
When a tree is felled so that its wood turns into a chair, for example, the carbon 14 that it has incorporated throughout its life will slowly disappear from the wood. As this happens at a known rate, it is possible to know when the tree was alive from the amount of carbon 14 in the wood.
Fortunately for researchers, it was possible to identify wooden artifacts made with metal instruments, which the Indigenous peoples of Canada did not have at the time. In other words, they could only have been created by the Vikings. The next step was to account for an anomaly in the amount of carbon-14 produced by cosmic rays, a type of radiation projected by the Sun and other stars towards Earth.
It turns out that a particularly strong “rain” of cosmic rays, when it hits carbon atoms, produces excess carbon-14. And other studies had already shown that one of these “storms” occurred in the year 993 AD. If it were possible to precisely identify this anomaly in the pieces of wood, the exact date of the Viking settlement would be easier to detect.
That’s what the researchers did – using wooden growth rings. Trees in different parts of the world can form rings of wood on their trunks as they grow, and each corresponds to a year.
Knowing that one of the inner rings corresponded to the year of the cosmic ray storm, and that the outermost wooden ring corresponded to the end of the tree’s growth, it was enough to count the other rings, to inside out, to conclude that the artifacts they had been made in A.D. 1021.
Accurate dating should help researchers better understand the context in which the Scandinavian colony was created and perhaps why it was ultimately abandoned.
“Coffeeaholic. Lifelong alcohol fanatic. Typical travel expert. Prone to fits of apathy. Internet trailblazer.”