Yesterday I made some stew using a Puerto Rican recipe called Bacalao guisado. Bacalao is the Spanish word for cured, salted codfish, and there's a lot of history around the trade and production of this specific fish product. Some of the most productive groundfish fishing grounds are found in the Grand Banks, the shallow ocean shelf off the coast of eastern North America. Hundreds of years ago, European (mainly Basque) fishermen traveled west over the Atlantic to fish for cod and set up shop on land to butcher and dry the fish before exporting it back to Europe. It was a valuable commodity as a food source for ships' crews, because it's non-perishable and easily packed into dense loads.
Back in those days, cod were so abundant that some sources describe an appearance of being able to walk across the water, over the backs of fish, who completely filled the water. Today, the cod fisheries in the Grand Banks region are so depleted from overharvesting that it is uncertain whether they will ever return to what they once were.