Jason Kingsley OBE of Modern History TV explained how eels were a dining staple of Medieval society and at one time became so valuable that they were used as payment for rent and for fines. Additionally, laws were made about where they could be fished. They finally went out of favor after King Henry I died after eating too many eels.
Henry the first king of England died because he ate too many eels. …His eldest son his only legitimate heir died earlier in the white ship disaster leaving a big gap in the succession for the throne of England. [Henry’s nephew}Stephen and [Henry’s daughter] Matilda were vying for the throne of England and that caused a period of chaos and disruption to this day called “The Anarchy”.