Viking Colonies Collapsed Through Over Hunting Walruses

Norsemen in exile from Iceland sailed to the shores of Greenland in the 10th century and survived thanks to the ivory of a unique species of walrus on the island. 

The precious material was traded throughout Europe in exchange for wood and iron and it allowed the Vikings to thrive in their desolate home. But just as swiftly as they arrived at the distant island in the Atlantic ocean, all signs of their occupation vanished in the 15th century. 

Experts now believe that their penchant for hunting walruses was ultimately their downfall as they forced the species to extinction, destroying their source of income. 

Norse people settled in Greenland in 950AD after Erik the Red was sent there in exile. By this point, much of Iceland’s native walruses had already been hunted to extinction by Vikings, and the new inhabitants in Greenland had inadvertently stumbled upon the next hunting ground.  

‘Our story starts where the Icelandic story ends. In Iceland, there are walrus finds in early Viking age sites,’ says Dr James Barrett, an academic from the University of Cambridge who led the study into the disappearance of Greenland’s Vikings. 

‘But later, they are described as a rarity. Previous research shows that the population of walruses in Iceland was hunted to depletion quite quickly after the Viking settlement.’

And it seems the Vikings did not learn from the lessons of Iceland, as a new study published in the scientific journal Quaternary Science Reviews reveals the same thing happened again. The demise of the Norse folk in Greenland was the very thing that helped them thrive — hunting walrus ivory.  

Academics at the universities of Cambridge, Oslo and Trondheim found that almost all ivory traded throughout Europe in Medieval times came from Greenland walruses.

After Iceland slaughtered its own populations of walruses, Greenland was, for centuries, the only source of the the valuable material. Norse settlements in the south-western region of the island held a monopoly on the material, which was in vogue throughout Europe. 

But as demand soared for the popular material, supply was dwindling and the Vikings forced further north in search of the animals they were overly reliant upon. 

At its peak, walrus ivory was a valuable medieval commodity, used to carve luxury items such as ornate crucifixes or the Viking game hnefatafl. 

The famous Lewis chessmen are made of walrus tusk. They showcase how the marbled effect of the ivory can be sculpted into various artefacts.  

The chessmen are thought to have been made in Trondheim shortly before 1200AD and discovered in the 1830s on the Isle of Lewis in the Outer Hebrides of Scotland. Scientists did not wish to destroy the rare tusks themselves so instead analysed parts of the walrus skull attached to the tusks.

A total of 67 of these skull fragments – known as rostra – were taken from sites across Europe, dating from between the 11th and 15th century.  Ancient DNA (25 samples) and stable isotopes (31 samples) extracted from samples of bone provided clues to the animals’ sex and origins.

It revealed that the Vikings became desperate for ivory and their journeys became longer, more arduous and less fruitful as numbers of mature male walruses dwindled. 

Scientists found that the hunters switched from hunting large males to settling for females and smaller animals. To compound the misery of the Pagan warriors, changing fashions and an emerging market for elephant ivory saw a rapid decline in demand of walrus ivory in the 15th century. 

Dr James Barrett said: ‘Walrus ivory was very popular and valuable especially early in the Middle ages, particularly for use in Romanesque art. 

‘But later, in the 1200s, there was a shift in popularity from walrus to elephant tusks around the time when Gothic art developed.’ With this major financial artery severed, the long-term habitation of Greenland was forced to an abrupt end, academics now believe.  

Dr James Barrett added: ‘Norse Greenlanders needed to trade with Europe for iron and timber, and had mainly walrus products to export in exchange.

‘We suspect that decreasing values of walrus ivory in Europe meant more and more tusks were harvested to keep the Greenland colonies economically viable.

‘Mass hunting can end the use of traditional haul-out sites by walruses.  ‘Our findings suggest that Norse hunters were forced to venture deeper into the Arctic Circle for increasingly meagre ivory harvests. 

‘This would have exacerbated the decline of walrus populations, and consequently those sustained by the walrus trade.’ It is thought that the lack of walruses was not the only issue but it at least played a significant role in the Viking withdrawal from Greenland. 

Other theories the collapse of the civilisation include climate change with the dawn of the ‘Little Ice Age’, unsustainable farming and the emergence of the Black Death.   

‘An overreliance on walrus ivory was not the only factor in Norse Greenland’s demise. However, if both the population and price of walrus started to tumble, it must have badly undermined the resilience of the settlements,’ says co-author Bastiaan Star of the University of Oslo.