The Holy Grail is a sacred object figuring in literature and certain Christian traditions, most often identified with the dish, plate, or cup used by Jesus at the Last Supper and said to possess miraculous powers. The connection of Joseph of Arimathea with the Grail legend dates from Robert de Boron's Joseph d'Arimathie (late 12th century) in which Joseph receives the Grail from an apparition of Jesus and sends it with his followers to Great Britain; building upon this theme, later writers recounted how Joseph used the Grail to catch Christ's blood while interring him and that in Britain he founded a line of guardians to keep it safe. The quest for the Holy Grail makes up an important segment of the Arthurian cycle, appearing first in works by Chrétien de Troyes.The legend may combine Christian lore with a Celtic myth of a cauldron endowed with special powers.
http://youtu.be/ABB8vcFds6g