The legend of the sunken city of Ys, the Breton Atlantis

The mythical tale that describes how the lost city of Ys was swallowed up by the waves of the ocean most likely derives from historical events that really happened around the fifth century AD, but, as Massimo Centini argues, for example, the moralistic emphasis of an event natural of limited proportions could reveal the attempt by the Christian invaders to strike at the previous Druid religion and its priestly class, especially the female one.