Fisher King

   The Fisher King is generally seen as the keeper of the Grail. He is sometimes called the Rich Fisher or Rich Angler. He might be an avatar of the Welsh Bran the Blessed. The Fisher king is the wounded occupant of the Grail Castle in Chrétien de Troyes's Perceval as well as in other works. The nature of the Fisher King's wound varies, but is generally seen as some form of castration or other loss of fertility. In the various versions of the Perceval Saga, Perceval sees a procession while at the Grail Castle, but fails to ask questions despite his curiosity. Perceval later discovers that if he had asked his questions, he would have discovered that the Fisher King was his uncle and Perceval would not have been forced to go on the Grail Quest. In Wolfram von Eschenbach's Perceval, The Fisher King is given the name Anfortas.
   Robert de Boron, in his Arthurian cycle, identifies the Fisher King with either Bron or Hebron and makes him Joseph of Arimathea's brother -in-law. (Note the similarity to Bran). In The Didot-Perceval, Perceval finishes his quest and returns to the Grail castle where he asks the proper question and in so doing Perceval restores the health of the Fisher King (read "fertility of the country").

(from http://camelot.celtic-twilight.com/camelot/infopedia/index.htm)