The most comprehensive account of the story of Arthur, the Round Table and the Grail is to be found in the work known as Lancelot-Grail or the Vulgate Cycle. It tells the story of the Arthurian world from the events of the Crucifixion, where the Grail originated, to the death of Lancelot after the destruction of the Round Table. It draws in many different strands, from the pseudo-historical stories about Arthur to the romances of chivalric adventure and the spiritual quest for the Grail. It consists of five works: the longest is Lancelot, a kind of chivalric history of the Round Table, which leads into the quest for the Grail and Arthur's death. The first two books were added later, and provide an account of events through Arthur's marriage and early military victories. Not long after the cycle was completed, another writer retained the first two books of the Vulgate Cycle but recast the last three books with a rather different emphasis; this version is known as the Post-Vulgate Cycle, and is one of the main sources used by Sir Thomas Malory. The History of the Holy Grail was written after the events described in Lancelot and The Quest for the Holy Grail were already an established part of the Arthurian story. It is, in Hollywood terms, a 'prequel', and relates the story of the Grail from its first appearance at the Crucifixion up to the point where it is placed by Alain, the Fisher King, in the castle of Corbenic, whose inhabitants then await the arrival of the chosen Grail knight.

Many points in the narrative are designed to foreshadow or to explain the later adventures connected with the Grail, but it also draws on the stories in the apocryphal gospels and other legends of the Crucifixion such as the story of Veronica, as well as unrelated material such as the story of Hippocrates. Less chivalric in tone than the subsequent books of the Vulgate Cycle, it also provides many details about the Grail itself which are not found elsewhere. Book jacket.