New dating of the Norse settlement of L’Anse aux Meadows in Newfoundland has determined that Vikings were present in North America exactly a thousand years ago, in AD 1021.
The discovery of L’Anse aux Meadows in the 1960s provided important archaeological evidence for Norse occupation in the region, supporting accounts in Icelandic sagas that refer to Viking voyagers travelling beyond Greenland to a place called Vinland, long believed to be North America. The UNESCO World Heritage Site was assumed to date to the end of the 1st millennium AD, based on stylistic analysis of the buildings and artefacts found there, as well as interpretations of the sagas written several centuries later, but until now precise dating was not possible.
The latest research has used a newly developed approach to radiocarbon dating, which is capable of dating objects to an exact year. It was applied to tree rings from pieces of wood from the site to determine exactly when it was occupied. Archaeologists selected four pieces of fir and juniper wood scrap that bore marks from metal tools, confirming that they had been worked by Vikings rather than by the indigenous people living in the area, and which still had their bark edges, as this was crucial for dating when the tree was felled.
It is known from reference material found around the world that in AD 993 there was a cosmic radiation event, probably a solar storm, which led to a significant spike in radiocarbon levels in the atmosphere. This spike can be detected in trees because of the radiocarbon absorbed by their tissues through photosynthesis, making it possible to date wood that grew around the time of the event. One of the four items from L’Anse aux Meadows did not have enough rings to reach the AD 993 anomaly, so was unsuitable for precise dating, but researchers were able to identify the event in the tree rings of the other items and conclude that all three trees were felled 28 years after this, in AD 1021.
Although this date does not disprove earlier assumptions that L’Anse aux Meadows was occupied at the end of the 1st millennium AD, it does raise some questions, as it was originally believed that the site was occupied for roughly a decade before being abandoned c.AD 1000. The new date, which is around 20 years after this, could indicate either that the site was occupied slightly later than previously thought, or that it was occupied sporadically for a longer period than was initially proposed. The details of the findings, the latest in a series of recent discoveries about America’s history, have been published in a paper in Nature.