Fishing for gold: how eels powered the medieval economy

And lords all across England wanted their share of this abundance. The 1086 Domesday survey has more records for rents of eels than of corn, and some of them were for quite impressive quantities of fish. The single largest Domesday rent came from the village of Harmston, in Lincolnshire, whose residents owed the Earl Hugh of Chester 75,000 eels annually. At the end of the 11th century there were more than 540,000 eels being paid as rent in England every year.

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Landlords collected eels to eat, but they also used them to pay their own debts. The Ramsey monks were due more than 70,000 eels each year from their tenants, and some of those fish were used to pay for things that the monastery needed. As we have seen, the monks sent 1,000 eels to Ralph Tuberville and his widow. And in the mid-11th century the Abbot of Ramsey agreed to pay 4,000 eels each spring to Peterborough Abbey for the right to take building stone from a quarry at Barnack. In early medieval England, eels could be both a meal and a de facto currency.

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However, people did not usually trade in live eels, or even freshly killed ones. In most cases the fish were cured, through some combination of salting, smoking and drying, so that they could be more easily transported and stored. The eels needed to be preserved so that tenants could keep them unspoiled until rent was due, and the landlords could then stockpile them until they were ready to be eaten. Most of the fish were caught in the autumn, during the yearly downstream migration, but the eel-rents were generally due at the start of Lent, so in late winter or spring.

Limiting the libido

Eel-rents were frequently due at this time because of the Lenten prohibition against eating meat. The church understood an explicit connection between meat (carnis) and carnality (carnalitas), believing that eating flesh meat – itself the product of sexual union – made one lusty. Carnal desires were to be suppressed during Lent, and even married couples were expected to practise abstinence. So carnis was off the table. Eating fish, however, was thought to not excite the libido in the same way and so was permissible. Eels were an especially good choice – eel pies, complete with pears and spices, abounded – because medieval Europeans believed that the fish reproduced asexually.

Eating eels was thought not to excite the libido, so they could be consumed during Lent

This idea goes back at least to Aristotle and results from an ancient misunderstanding of the eels’ mysterious life cycle. Eels breed in the open Atlantic – likely in the Sargasso Sea – before migrating to land and heading upriver as small (10cm or shorter) fish called elvers. Once they find suitable homes inland, eels stay and grow for more than a decade, until they eventually head back to sea to breed and die. Aristotle, who never made the connection between elvers and eels, wrote that the fish spring spontaneously out of the mud. Other ancient writers such as Pliny the Elder and Athenaeus followed Aristotle in asserting eels’ asexual reproduction. This belief became so well-established in the European imagination that it persisted into at least the 16th century.

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Part of the reason for this belief sprang from the fact that eels only develop obvious ovaries and testes at the very end of their lives, just before they head back out to sea. Aristotle looked unsuccessfully for eels’ reproductive organs, and he was not alone. It was not until 1777 that an Italian named Carlo Mondini located eels’ ovaries, and the search for their testes frustrated researchers – including Sigmund Freud – for a further 120 years. To medieval observers, not only did the fish not visibly reproduce, but they seemed to lack the means for doing so. Therefore, relying on classical authorities and their own experiences, Europeans in the Middle Ages believed eels to be asexual. And this made them excellent Lenten fare.

Dying demand

Eels’ religious utility helps to explain the longevity of eel-rents in England. Most other in-kind rents had disappeared by the 13th century, but landlords continued to collect eel-rents in large numbers. Records from the 13th century show more than 450,000 eels being paid annually, with new rents still being initiated. The real decline in eel-rents came during the 14th century, with the dietary and monetary changes that followed the Black Death. After 1349 red meat became increasingly available to more people, as empty farmland was given over to pasturage. At the same time, the decreased population meant that there was more currency per capita in the system. Demand for eels dropped, and the century shows eel-rent totals of only about 34,000 fish. The 15th century saw a still sharper drop, and by 1500 eel-rents had largely disappeared.

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The real decline in eel-rents came in the 1300s, with the changes that followed the Black Death

A few did hold on, though. In the 1680s a mill in Norfolk still rented out for £30 and 60 eels. But the mill’s landlords – the Wyndham family of Felbrigg Hall – had frequent trouble collecting their payment. Eel-rents had deep historical traditions, going back to Domesday and even earlier. And the Wyndham’s miller, it seems, felt that they belonged firmly in the past.

John Wyatt Greenlee holds a PhD in medieval studies from Cornell University. He studies eels in English history and tweets as the Surprised Eel Historian @greenleejw. To find out more about eel-rents, visit John Wyatt Greenlee’s website

This article was first published in the October 2020 edition of BBC History Magazine