Chevalere Assigne

The story of the Knight of the Swan, or Swan Knight, is a medieval tale about a mysterious rescuer who comes in a swan-drawn boat to defend a damsel, his only condition being that he must never be asked his name.

The earliest versions (preserved in Dolopathos) do not provide specific identity to this knight, but the Old French Crusade cycle of chansons de geste adopted it to make the Swan Knight (Le Chevalier au Cigne, first version around 1192) the legendary ancestor of Godfrey of Bouillon. The Chevalier au Cigne, also known as Helias, figures as the son of Orient of L'Islefort (or Illefort) and his wife Beatrix in perhaps the most familiar version, which is the one adopted for the late fourteenth century Middle English Cheuelere Assigne. The hero's mother's name may vary from Elioxe (probably a mere echo of Helias) to Beatrix depending on the text, and in a Spanish version, she is called Isomberte.

At a later time, the German poet Wolfram von Eschenbach incorporated the swan knight Loherangrin into his Arthurian epic Parzival (first quarter of the 13th century). A German text, written by Konrad von Würzburg in 1257, also featured a Swan Knight without a name. Wolfram's and Konrad's were used to construct the libretto for Richard Wagner's opera Lohengrin (Weimar 1850).

Another example of the motif is Brangemuer, the knight that lay dead in a boat tugged by a swan, and whose adventure was taken up by Gawain's brother Guerrehet (Gareth or Gaheris) in the first Continuation to Chrétien de Troyes' Perceval.

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Wikipedia