An interesting point about fish in medieval times is that sea birds were regarded and actually classed as fish. This was because they were deemed to have been created at sea.
Included under the term of 'fish' were seabirds such as puffins and barnacled geese.
The most common fish eaten by people in medieval Europe, particularly medieval Britain, were salted fish and pickled herrings. The English herring fleet fished in the summer and the fish caught were preserved so as to provide sustenance to the population through the winter. Sometimes dried cod was available – called stockfish – but generally speaking there was little else by way of seafood.
There was so much salted fish in the average medieval diet that people took to cooking sauces as an accompaniment to make the fish more palatable. Herbs and spices were the main ingredients for these sauces and it is believed this is the origin of parsley sauce in English cooking. Read more about medieval sauce recipes and medieval herbs. People who lived at the coast had a little more choice by way of fresh oysters and whelks. Freshwater fish were an option for people living inland. These included:
Wealthy landowners had the most plentiful supplies of freshwater fish on their estates; some even had their own fish farms, breeding carp and pike.
Fish was generally cooked by boiling in a mixture of water, salt and ale and the resulting impurities skimmed off before serving. Sometimes fish was also fried. Today’s modern cooking methods encourage us to simmer or poach most fish, though frying is still an option.