In the late fourteenth century, the Anglo-Norman author Jean d’Arras, at the behest of the Duc de Berry, wrote an account of the fantastic ancestry of the House of Lusignan: Specifically, Count Raymond of Poitou had married a fey woman, Melusine, upon condition that he never observe her on a Saturday, and their union produced a number of children before the count was tempted to spy upon his wife and eventually, after discovering her secret (on Saturdays, she was a serpent from the waist down), he lost her forever. In the meantime and thereafter, however, their offspring adventured both at home and abroad and came to power in places as various as Armenia, Cyprus, and Luxembourg, and their son Geoffrey of the Great Tooth both committed fratricide and endeavored to atone for it, while accomplishing other feats as well. Sometime in the fifteenth century, an anonymous translator rendered the tale into Middle English, albeit in an idiosyncratic form that makes for difficult reading, and this version was edited by Walter W. Skeat for the Early English Text Society many years ago. Overall, it’s not a particularly cheerful tale, but it likely will be of some interest to those keen on foundation myths and family histories, or with a liking for tales of dealings between mortals and fairies. Mildly recommended at best.

Featured image: Raymond walks in on his wife, Melusine, in her bath and discovers she has the lower body of a serpent. Illustration from the Le livre de Mélusine, 1478. By an anonymous engraver working for the workshop of the printer Adam_Steinschaber. The original is held by the Bibliothèque nationale de France, but, per Wikipedia, it may be copied from the website of the Library of Congress: https://www.loc.gov/exhibits/bnf/bnf0004.html#obj47.
Original printed source: Jean d’Arras, Histoire de la belle Melusine, Genève, Adam Steinschaber, août 1478, fol 142r – list of known copies: ISTC; USTC, Public Domain, Link.