DNA study of Viking cod reveals secrets of fishing trade more than 1,000 years ago
New research shows Europe-wide fish trade has been going on for more than a thousand years, and was started by Norwegian fishermen.
Tough vikings braved the chilly Arctic waters in longboats to bring back hauls of delicious cod - which were traded as far away as Spain and Italy.
The new study. published in the journal PNAS, suggests that some form of this pan-European trade in Norwegian cod may have been taking place for 1,000 years.
Latest research from the universities of Cambridge and Oslo, and the Centre for Baltic and Scandinavian Archaeology in Schleswig, used ancient DNA extracted from the remnants of Viking-age fish suppers.
Traded fish was one of the first commodities to begin to knit the European continent together economically
The study analysed five cod bones dating from between 800 and 1066 AD found in the mud of the former wharves of Haithabu, an early medieval trading port on the Baltic.
Haithabu is now a heritage site in modern Germany, but at the time was ruled by the King of the Danes.
The DNA from these cod bones contained genetic signatures seen in the Arctic stock that swims off the coast of Lofoten - which is still a centre for Norway's fishing industry.
Vikings braved the chilly Arctic waters in longboats to bring back hauls of delicious cod
Researchers say the findings show that supplies of 'stockfish' - an ancient dried cod dish popular to this day - were transported over a thousand miles from northern Norway to the Baltic Sea during the Viking era.
Prior to the latest study, there was no archaeological or historical proof of a European stockfish trade before the 12th century.
The small size of the current study prevents researchers from determining whether the cod was transported for trade or simply used as sustenance for the voyage from Norway.
They reckon the Haithabu bones provide the earliest evidence of fish caught in northern Norway being consumed on mainland Europe - suggesting trade involving significant distances has been in operation for a millennium.
Dr James Barrett, senior author of the study from the University of Cambridge's McDonald Institute for Archaeological Research, said: "Traded fish was one of the first commodities to begin to knit the European continent together economically.
"Haithabu was an important trading centre during the early medieval period.
"A place where north met south, pagan met Christian, and those who used coin met those who used silver by weight.
"This Arctic stock of cod is still highly prized - caught and exported across Europe today.
One of the ancient Viking cod bones used in the study
'This Arctic cod is still highly prized - caught and exported across Europe today' says Dr Dr Barret
"Our findings suggest that distant requirements for this Arctic protein had already begun to influence the economy and ecology of Europe in the Viking age."
Stockfish is white fish preserved by the unique climate of north Norway, where winter temperature hovers around freezing.
Cod is traditionally hung out on wooden frames to allow the chill air to dry the fish.
Some medieval accounts suggest stockfish was still edible as much as ten years after preservation.
Dr Barrett added: "The Viking world was complex and interconnected.
"This is a world where a chieftain from north Norway may have shared stockfish with Alfred the Great while a late-antique Latin text was being translated in the background.
"A world where the town dwellers of a cosmopolitan port in a Baltic fjord may have been provisioned from an Arctic sea hundreds of miles away."