A proper understanding of the significance of the cultic object called the Holy Grail has eluded most scholars who have confined their research to western European literary and cultural sources, especially since the originally Celtic story of the Holy Grail underwent numerous bewildering metamorphoses in the romances of the Middle Ages.

It was the Indologist Leopold von Schroeder's reading of the Grail story (1910) in the light of his knowledge of Indic mythology that first achieved a dramatic expansion of the field of Holy Grail scholarship. The only other scholar who developed a...