The central quest in the Arthurian tales is the search for the Holy Grail, the cup said to have been used by Jesus at the Last Supper and by Joseph of Arimathea to catch the blood of Jesus as he hung on the cross. The tradition was that Joseph, who had provided a tomb for Jesus, had come to Britain with the Grail.

The Grail quest was undertaken in Arthur’s name by knights of the king’s court, the Round Table fellowship. In the Later Arthurian Tales of the Mabinogion, for instance, Peredur, Son of Efrawg, the Welsh version of the hero Percival (Parsifal), searches for the Grail. In other versions of the Arthurian romance, questers include Gawain and Galahad. The heroes are always tested during their quests. They face such figures as the Fisher King, the wounded guardian of the Grail, whose wound affects the fertility of the land he rules. If the questing hero does not ask him certain questions, he and his land may be doomed to infertility, and the Grail may not be fully achieved. Or the hero—even Arthur himself—can be tested by a femme fatale such as Arthur’s half-sister Morgan Le Fay.