There is a curious tale attached to the village of Orford in Suffolk which took place during the reign of King Henry II (1154-1189). Orford Castle (a stronghold against the treacherous Hugh Bigod of Bungay) the strange polygonal keep was then under the care and management of Bartholemew de Glanville a local man, in the service of the crown. The event was actually documented in the “Chronicon Anglicanum” a history of England written by Ralph of Coggeshall a medieval chronicler some forty years after the occurence took place.
One day around 1204AD the local fishermen of Orford caught what they believed to be a merman in their nets. They were extremely surprised when they finally managed to get their catch aboard because there, in the bottom of their boat, was a man staring angrily back at them.
He was described as being naked, but with a hairy body, as having a long straggly beard with an excessively hairy chest. The fishermen took the creature to the castle where Bartholemew de Glanville imprisoned it in the dungeons.
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Thanks again to Gavin for the mermaid lore.