Cod: History and Origins

Few foods have moved more history than a plain white fish. Cod is not an invention and has no discoverer — it is a wild cold-water fish that people around the cold North Atlantic learned to catch, dry, and trade over more than a thousand years. Long before refrigeration, a fillet of cod could be turned into a hard, light, almost imperishable food that travelled for months. That single fact — cheap protein you could carry across an ocean — helped feed Viking voyages, build the trading wealth of medieval Europe, draw the first Europeans to the coasts of North America, and, in the end, collapse one of the greatest fisheries the world has ever known. This article traces what the historical and scientific record actually supports: where cod was caught and how it was preserved; how the dried-cod trade spread; cod's long career as a global commodity and a religious food; the rise of cod liver oil as a folk and then medical remedy; and the modern story of overfishing and the 1992 Newfoundland collapse. Where the record is firm we say so; where a date or a quotation is uncertain or traditional, we name it as such.

Table of Contents

  1. What Cod Is, and Where It Lives
  2. Stockfish: The Viking Travel Food
  3. A Medieval Commodity: Bergen and the Hanseatic Trade
  4. Salt Cod: Basques, Religion, and the Bacalao World
  5. Cabot, the Grand Banks, and the New World Fishery
  6. Cod Liver Oil: From Folk Remedy to Vitamin D
  7. Overfishing and the 1992 Collapse
  8. A Fish That Changed the World
  9. Research Papers and References
  10. Connections
  11. Featured Videos

What Cod Is, and Where It Lives

Cod is a wild, cold-water, bottom-dwelling fish of the genus Gadus. The fish at the centre of this history is Atlantic cod, Gadus morhua, formally named by the Swedish naturalist Carl Linnaeus in 1758. Its close relative Pacific cod, Gadus macrocephalus, lives on the far side of the world in the North Pacific. Atlantic cod ranges across cold northern waters — in the eastern Atlantic from the Bay of Biscay north to the Arctic Ocean, including the Baltic and North Seas and the waters around Iceland and the Barents Sea, and in the western Atlantic around Greenland, Labrador, and the banks off Newfoundland and New England.

Two features of the fish made it historically priceless. First, cod is enormously abundant when its stocks are healthy: it spawns in vast aggregations, and for centuries fishermen described waters that seemed almost solid with fish. Second, cod is a lean white fish — its flesh is nearly fat-free — which means that, unlike oily fish such as herring or salmon, it can be dried hard without turning rancid. A food that is both plentiful and easy to preserve is exactly the kind of food that builds trade routes, and cod did. This page is the longer story behind the brief origin note on the main Cod page.

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Stockfish: The Viking Travel Food

The oldest chapter in cod's human story belongs to the cold coasts of Norway. There, the simplest possible preservation method works almost perfectly: split the fish, hang it on wooden racks in the cold, dry late-winter air, and let the wind and frost do the rest. The result is stockfish — cod dried until it is hard, light, and so stable it can keep for years without salt. Because the lean flesh holds almost no fat to spoil, no refrigeration is needed; the fish is simply soaked back to life in water before cooking.

This dried cod is widely described as part of Norwegian life and trade since the Viking Age, roughly from around 800 CE onward, and stockfish is often called Norway's oldest export product still traded today. The picture commonly drawn is intuitive and well supported in outline: Norse seafarers needed a durable, high-protein food that could survive long open-boat voyages, and stockfish fit that need exactly. The great seasonal cod runs to the Lofoten Islands in northern Norway — where mature cod stream down from the Barents Sea each winter to spawn — became, and remain, one of the most important fisheries in the country's history. The exact extent of Viking-era long-distance stockfish trade (as opposed to local use and provisioning) is something historians and, more recently, ancient-DNA researchers are still refining; what is not in doubt is that air-dried cod was a foundational food of the medieval Norse world.

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A Medieval Commodity: Bergen and the Hanseatic Trade

By the High Middle Ages, dried cod had grown from a travel ration into one of the major commodities of northern Europe. The Norwegian port of Bergen became the great gathering point: fishermen from Lofoten and the northern coasts brought their stockfish south to Bergen, where merchants bought it and sent it onward across the North Sea, the Baltic, and as far as the Mediterranean. From the thirteenth century onward this trade was dominated in large part by the Hanseatic League, the powerful confederation of northern German and Baltic trading towns, which ran a major trading post (the Kontor) at Bergen and made stockfish one of its staple goods.

How far and how early this trade reached has recently been tested with genetics. A 2022 ancient-DNA study by Lourdes Martínez-García and colleagues, published in Proceedings of the Royal Society B, analysed cod bones from medieval European sites and found a clear shift over time: cod eaten in eleventh- and twelfth-century London came mostly from nearby waters, but by the thirteenth and fourteenth centuries Londoners were eating cod from distant sources, including Arctic Norway and Iceland. The authors place the export of Icelandic cod — reaching England by way of Norway and Bergen, on Norwegian, English, and Hanseatic ships — at around 1300 CE or earlier. In other words, hard scientific evidence confirms what the documents suggest: a genuinely long-range, globalised cod trade was running across medieval northern Europe centuries before the Atlantic crossings.

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Salt Cod: Basques, Religion, and the Bacalao World

Drying alone works best in cold, dry northern air. Further south, and at sea, a second method took over: salting. Salt draws the water out of the flesh and, combined with drying, produces salt cod — the bacalao of Spain, bacalhau of Portugal, klippfisk of Norway, and morue of France. The Basques, a seafaring people of the western Pyrenees on the border of modern Spain and France, became especially associated with salt-cod fishing and curing, and by the late medieval and early-modern period they were fishing cod on a large scale, including in the rich waters of the western Atlantic.

Salt cod found an enormous and reliable market because of religion. The medieval Catholic calendar set many fast days — Fridays, Lent, and other observances — on which the faithful were to abstain from meat, but fish was permitted. A cheap, storable, long-lasting fish that could be shipped far inland and kept for months was therefore in steady demand across Catholic Europe. Salt cod also became a staple ration for ships, armies, and, later, the plantation economies of the Atlantic world. From the Iberian Peninsula it spread along trade routes to West Africa, the Caribbean, and Brazil, where dried salt cod remains a defining ingredient of national cuisines to this day. The brief culinary note on the main Cod page — bacalao, brandade, fish and chips, lutefisk — is the living legacy of these centuries of preservation.

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Cabot, the Grand Banks, and the New World Fishery

The search for cod helped pull Europe across the Atlantic. The richest cod grounds in the world lay over the Grand Banks, the broad, shallow continental shelf off Newfoundland, where cold and warm currents meet and feed gigantic stocks of fish. There is a real possibility that Basque and other fishermen were quietly working these western waters before they were formally "discovered," though firm documentary proof of pre-Columbian European cod fishing on the Banks is debated.

The famous documented moment came in 1497, when the Italian navigator John Cabot (Giovanni Caboto), sailing under an English commission, reached the coast of Newfoundland. The most-quoted record of the fishery's abundance is a letter written that December by Raimondo de Soncino, the Milanese ambassador in England, reporting Cabot's claim that the sea there was so full of fish that they could be taken "not only with the net, but in baskets let down with a stone." Those fish were cod. Within a few decades, fishermen from England, France, Spain, and Portugal were crossing every year to fish the Banks, using two main methods: the "wet" or "green" fishery, in which cod were heavily salted on board and carried home to be dried; and the English "dry" fishery, which used shore stations in Newfoundland where the catch was lightly salted and dried on wooden racks called flakes. This seasonal migration of fishing fleets across the Atlantic became one of the great economic engines of the early-modern world, and the cod trade was woven deeply into the settlement of Newfoundland and New England.

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Cod Liver Oil: From Folk Remedy to Vitamin D

Cod gave the world more than food. The oil pressed from cod livers became one of history's most important traditional remedies — and, eventually, a turning point in the science of nutrition. In the fishing communities of northern Europe, cod liver oil had a long folklore use, rubbed on aching joints and swallowed for rheumatism and gout. In later eighteenth-century Britain, physicians at the Manchester Infirmary began using it internally for chronic rheumatism; the Manchester physician Thomas Percival documented its effects, and by this period cod liver oil had entered local medical practice. (Secondary histories differ on the precise dates and on exactly who introduced it — figures such as Samuel Kay are also credited — so the safest statement is that its medical use took hold at the Manchester Infirmary in the later 1700s.)

Its most famous use was against rickets, the bone-softening disease of children that was rampant in the smoky, sunless industrial cities of the nineteenth century. Doctors observed that children given cod liver oil tended not to develop rickets, and oral use for this purpose spread — according to standard histories, beginning in Germany in the 1820s and reaching other countries through the 1860s. At the time, nobody knew why it worked. The answer came in the twentieth century. In 1914 the American researchers Elmer McCollum and Marguerite Davis identified a fat-soluble factor in cod liver oil that became known as vitamin A. Then, in 1922, after Edward Mellanby's experiments linking diet to rickets, McCollum tested cod liver oil whose vitamin A had been destroyed and found it still cured the disease — revealing a separate factor he named vitamin D, the fourth vitamin to be named. Cod liver oil was thus the very substance through which vitamin D, the "sunshine vitamin" whose deficiency causes rickets, was discovered. The detailed nutrition is covered in the companion Cod Benefits articles; here it is enough to mark that a humble fishing by-product helped found modern vitamin science.

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Overfishing and the 1992 Collapse

For most of its history the cod fishery seemed limitless — an inexhaustible bank that fed Europe and the Americas for five centuries. In the twentieth century that illusion ended. After the Second World War, industrial fishing transformed the hunt: enormous factory trawlers with sonar, freezers, and the power to drag the bottom could take more cod in an hour than an old sailing vessel took in a season. Stocks that had been fished for a thousand years began to crash.

The most dramatic collapse was off Newfoundland. The spawning biomass of the northern cod stock fell by roughly 93 percent in just thirty years — from about 1.6 million tonnes in 1962 to somewhere between 72,000 and 110,000 tonnes by 1992. On 2 July 1992, the Canadian government declared a moratorium, banning the commercial northern cod fishery off Newfoundland and Labrador. It was the largest industrial closure in Canadian history: by various accounts it put on the order of 19,000 fishing and processing workers directly out of work, with tens of thousands more jobs lost indirectly, and gutted hundreds of coastal communities whose entire way of life had been built on cod. The moratorium was expected to last about two years; in fact the stock stayed critically low for decades and the fishery remained largely closed far longer, a sober warning about how even a seemingly endless natural resource can be exhausted. Today, sustainable-seafood guidance generally steers buyers toward well-managed sources such as Alaskan Pacific cod and Icelandic and Norwegian Atlantic cod from stocks rebuilt under strict quotas — a point discussed further on the main Cod page.

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A Fish That Changed the World

Pull the threads together and cod's historical importance is hard to overstate. Because a lean white fish could be dried or salted into a food that lasted for months and crossed oceans, cod became one of the first truly global commodities — the protein that provisioned Norse voyages, enriched the medieval Hanseatic ports, fed Catholic Europe through its fast days, and lured European fleets to the New World, where the cod trade helped seed the settlement of Newfoundland and New England. The writer Mark Kurlansky captured this in the very title of his 1997 history, Cod: A Biography of the Fish That Changed the World — not hyperbole so much as plain economic history.

The story's ending carries the lesson. The same fish that built economies became, in the late twentieth century, the textbook example of a fishery destroyed by its own success. Cod's history is therefore two stories in one: a celebration of human ingenuity in turning a wild animal into durable, tradeable, life-sustaining food — and a cautionary tale about the limits of the sea. Knowing both is the point of telling the history at all. For the nutrition, the modern science, and practical guidance, see the companion Cod Benefits articles and the main Cod page.

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Research Papers and References

The list below combines peer-reviewed research with reputable history and food-science sources, plus curated PubMed topic-search links. Historical primary sources (such as the December 1497 letter of the Milanese ambassador Raimondo de Soncino reporting John Cabot's voyage) are named in the article as historical sources rather than as modern citations. Author names, titles, and journals are given as plain text; only the stable DOI, PMID, or archive link is hyperlinked, and each opens in a new tab.

  1. Martínez-García L, Ferrari G, Oosting T, et al. Ancient DNA evidence for the ecological globalization of cod fishing in medieval and post-medieval Europe. Proceedings of the Royal Society B: Biological Sciences. 2022;289(1985):20221107. — doi:10.1098/rspb.2022.1107
  2. Hernigou P, Auregan JC, Dubory A. Vitamin D: part II; cod liver oil, ultraviolet radiation, and eradication of rickets. International Orthopaedics. 2019;43(3):735-749. — doi:10.1007/s00264-019-04288-z
  3. Kurlansky M. Cod: A Biography of the Fish That Changed the World. Walker and Company; 1997. (Popular history; ISBN 978-0-8027-1326-1.)
  4. Cod fishery collapse of 1992. Encyclopædia Britannica. — britannica.com: cod-fishery-collapse-of-1992
  5. Cod liver oil — folklore, medical history, and vitamin discovery. Wikipedia. — en.wikipedia.org: Cod liver oil
  6. Atlantic cod fishery — history and trade — PubMed: Atlantic cod fishery history and ancient DNA
  7. Cod liver oil, vitamin D, and rickets — history — PubMed: cod liver oil, vitamin D, and rickets history

External Authoritative Resources

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Connections

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