The Grail legend started as a Celtic myth in the Middle Ages when stories about the feats of king Arthur were circulating among the populace as a part of their oral tradition. The first documented work on this, Historia regum Brittaniae was written by Geoffrey of Monmouth between A.D. 1135 and 1139 in which he related the story of how the great king defeated the Romans in eastern France.

The association of the Grail with king Arthur started with Chrétien de Troyes who wrote the earliest extant work on the Grail. He claimed to have had as his source for the story one Count Philip of Flanders. This work, Conte del Graal, written at about 1190 A.D. was left unfinished but was continued by four different authors who gave different endings to it and only in the third of the continuations written by Manessier around 1230A.D., did Parsifal achieve the Grail.

After Chrétien came Wolfram von Eschenbach’s Parzival written between A.D. 1200 and 1210 and was one of the most celebrated romances of the time and has been considered by some to be of profound mystical significance.

The source of Eschenbach’s work is not known but he may or may not have borrowed from Chrétien. Their hero, called Perceval by Chrétien and Parzival by Wolfram had the same qualities of innocence and guilelessness. Only their views about the nature of the Grail differed with Wolfram calling it a stone which falls from heaven and Chrétien declaring that it was a large bowl or chalice.

In the 13th century came the Welsh romance Peredur which obviously had a similar origin with the work of Chrétien as the body of the work and the hero are the same. In fact it could be said that Chrétien’s work was derived from the Celtic oral tradition which already may have had this character in it.

Before Chrétien, the Grail was not considered to be a Christian symbol and he did not make much of an attempt to explain the Grail and the lance in a significantly Christian way. That was left to another medieval writer Robert de Boron whose work, Joseph d’Arimathie was written at about 1200A.D. De Boron was actually the first through this work to provide a coherent explanation of what the Grail and the lance were and their significance. He drew heavily from the apocryphal works Acts of Pilate and Gospel of Nicodemus(4th and 5th centuries).

De Boron claimed that his work was inspired and had been revealed to him by an Angel. He therefore initiated a chain of events which led to a total adoption of the Grail and the lance by the Christian faith. His assertion that the Grail was the cup which had been used by Jesus and His disciples for the Last Supper and in which His Blood was caught while He was being prepared for burial was apparently carried to its logical conclusion when the Queste del Saint Graal was completed in 1210A.D.

With the appearance of this body of work written probably by French monks, the Grail came to be fully interpreted in the light of Christian tradition. It fully became the cup of the Last Supper and the Spear became the lance that the Roman soldier, Longinus had used in piercing the side of Jesus.

According to de Boron, Joseph of Arimathea had requested the body of Jesus from the Roman authorities so that he could bury it. While he was bathing this body, some blood trickled out from the wound, which Jesus sustained on the cross through the spear of the Roman soldier. He collected the blood in the cup which had previously been used by Jesus and His disciples during the Last Supper.

When Jesus’ body disappeared, however, Joseph was accused of stealing it, arrested by the Jewish authorities and jailed. While in jail, though he was deprived of food, he miraculously survived as a result of a wafer being dropped daily by a dove into the cup which he had with him. While in prison, Jesus appeared to him in a vision and entrusted the holy spear and the cup to him for safekeeping. Joseph thereafter journeyed westwards and established a church in Glastonbury, England dedicated to the Virgin Mary.

The Grail Order was born and a succession of guardians followed until we reach the Arthurian age when the Grail became associated with him. There have also been a succession of tables where the guardians sit to celebrate the holy Mass. The first Table was established by Joseph of Arimathea and his followers and only twelve may sit at this table representing the twelve disciples of Christ.

The thirteenth seat was not occupied and it became known as Siege Perilous after one of them was swallowed up as he tried to sit on it. This seat represented that of Judas. In some versions of the story, Joseph did not reach Britain, but made his stop somewhere in Europe and was succeeded by his sister’s husband Bron who established the second Table on the Mountain of Salvation which was identified to be in France and this man Bron in this version became the Fisher king and highest guardian of the Grail.

The third Table called the Round Table was formed for king Arthur by Merlin, the magician but the Grail was absent. It was said to have made a brief appearance at the Round Table at Pentecost and the sight was so magnificent that most of Arthur’s knights pledge their lives to the pursuit of this mysterious object. The guardianship of the Grail required the highest degree of chastity and according to tradition, only the purest of men could be the guardians.

In return for their purity, the Grail conferred blessings upon the land and was visible to all. The Grail withdrew its presence from humanity, however, when its highest guardian in one version looked lustfully at a maiden who had come to worship, the lance fell on him spontaneously inflicting a deep wound that would not heal and from then on he was referred to as the maimed or wounded king. Therefore, by the time of king Arthur, the Grail had withdrawn its presence and was no longer to be seen, hence the quest for it when it made its brief appearance.

Merlin, the magician and prophet had sent a message to king Arthur telling him that the time was ripe to set about the quest for the Grail and the knight who would achieve this quest was already born and of the right age. With king Arthur and his knights, the stage was set for what was to be one of the most important if not the most important medieval quest. The very last of the medieval writers to concern himself with the Grail was Sir Thomas Mallory who transmitted the legend to English-speaking peoples. His work Morte d’Arthur was more of a chronicle of the history and achievements of king Arthur than it is a romance about the Grail.