On 8 July Christie's will auction a rarest illuminated manuscript of the early fourteenth century, the Clermont-Tonnerre Grail, containing the first three texts of the Lancelot cycle

The estimate for the book is £1.5–2 million.

The manuscript has spent 700 years in private hands, has never been publicly exhibited and has never been studied academically. It is now the earliest of the three privately owned copies of the cycle among the two hundred or so known.

It is a prose trilogy in Old French: the history of the Grail, the origins of Merlin, and his adventures together with Arthur. The corpus of texts was created in the thirteenth century for an aristocratic audience and laid claim to being a historical chronicle. Arthur appears in it not as a fairy-tale figure but as a king with a genealogy, court protocol and diplomatic missions. To the medieval reader these texts were offered very much as a historical monograph would be, only one about times that had taken place no one knew quite when.

The miniatures are attributed to the Master of the Liège Apocalypse, an anonymous illuminator of distinctive manner.