6. King Henry I of England died after eating ‘a surfeit of Lampreys’, causing a civil war
After Henry I’s male heir died in 1120, he spent many years trying to have another. When success looked increasingly unlikely, he made the controversial move of naming his daughter, Matilda, as his heir. He got all his barons to swear loyalty to her and thought the matter settled. In November 1135, Henry followed a day’s hunting with a hearty dinner. But after gorging himself on lampreys, an eel-like fish, he died. The official cause of death: ‘a surfeit of lampreys’. Perhaps inevitably, many barons broke their promise to support Matilda, and a long and brutal civil war erupted.