Authenticity and Scholarship

There is no tradition of a single, continuously venerated Grail object to authenticate, and scholarship treats the Grail first of all as a literary phenomenon. Studies such as Roger Sherman Loomis's trace its development out of Celtic myths of magical vessels and cauldrons of plenty, Christianized by Robert de Boron into the cup of the Last Supper; the debate among specialists is over these literary and mythological roots, not over a physical relic.

The several cups later claimed as the Grail, the Santo Caliz of Valencia, the Sacro Catino of Genoa, the Nanteos Cup of Wales and others, are real objects with their own histories, but none is documented back to the first century or evidentially connected to Jesus, and they cannot all be the Grail in any case. Because no physical object is established and the Grail's existence as a relic is unproven, it is classed as legendary in existence and debated in authenticity.