Ys
Ys (also spelled Is or Ker-Ys in Breton) is a mythical city built in the Douarnenez bay in Brittany by Gradlon, King of Cornouaille, for his daughter Dahut.
According to the legend, Ys was built below sea level, protected from inundation by a dam. The only keys of the gate in the dam were held by Gradlon, but Satan made Dahut steal them and give them to him. He then opened the gate and Ys was flooded. In some versions of the story, Satan was sent by God to punish the city, whose inhabitants were becoming decadent. Other versions of the story tell that Dahut stole the keys either at her lover's request or in order to open the gates of the city to let her lover in. The only survivors were the King Gradlon, who was advised to abandon his daughter by Saint Winwaloe, and Saint Winwaloe himself. Gradlon then founded Quimper and on his death, a statue representing him on horseback looking in the direction of Ys was erected on the Saint Corentin Cathedral and still stands there. Bretons said that Ys was the most wonderful city in the world, and that Lutèce was renamed Paris after Ys was destroyed, because "Par-Is" in Breton means "Similar to Ys".
This deluge legend differs from others because the location of Ys is well defined: the statue of Gradlon looks at it, most of the localities mentioned exist, several Roman roads actually lead into the sea (and are meant to lead to Ys), and this myth could in fact depict the engulfment of a real city during the 5th century. This history is also sometimes viewed as the victory of Christianity (Gradlon was converted by Saint Winwaloe) over druidism (Dahut and most inhabitants of Ys were worshippers of Celtic gods). However, a Breton folktale asserts that Gradlon met, spoke with and consoled the last Druid in Brittany, and oversaw his pagan burial, before building a chapel in his sacred grove.
The legend of Ys was confined to the folk of Brittany until 1839, when T. Hersart de la Villemarqué published a collection of popular songs collected from oral tradition, the Barzaz Breizh. The collection achieved a wide distribution and brought Breton folk culture into European awareness. One of the oldest of the collected songs was this tale. The medieval poet Marie de France also wrote poetry and stories based around the Ys legend. Four years after Luminais' painting scored a success at the Salon of 1884, on May 7, 1888, Édouard Lalo's opera Le Roi d'Ys, based on this legend, premiered in Paris. In Claude Debussy's first book of Preludes (published 1910), the evocative La Cathédrale engloutie recalls the drowned cathedral in the city of Ys, with the muffled and watery sonority of its spectral bells.
Poul Anderson and his wife Karen wrote a tetralogy of novels about Ys in the 1980s.