<human>:  Was the subject of Parsifal taken from British folklore?
<bot>: Yes, the subject of Parsifal, an opera in three acts by Richard Wagner, was taken from British folklore. Parsifal was loosely based on a poem about Percival, a Knight of the Round Table. King Arthur and the Knights of the Round Table were products of British folklore, so the subject of Parsifal was taken from British folklore.