Merlin (Robert de Boron poem)

Merlin is a partially lost French epic poem written by Robert de Boron in Old French and dating from around the end of the 12th century to the beginning of the 13th century. The author reworked Geoffrey of Monmouth's material on the legendary Merlin, emphasizing Merlin's power of prophesy and linking him to the Holy Grail. The poem tells of Merlin's origin and early life as a redeemed Antichrist, his role in the birth of Arthur, and how Arthur became King of Britain. Merlin's story relates to Robert's two other reputed Grail poems, Joseph d'Arimathie and Perceval. Its motifs became popular in medieval and later Arthuriana, notably its introduction of the sword in the stone legend, its redefinition of the Grail, and its turning the previously peripheral Merlin into a key character in the legend of King Arthur.

The poem's medieval prose retelling and continuations, collectively the Prose Merlin, became parts of the 13th-century Vulgate and Post-Vulgate cycles of prose chivalric romances. The Prose Merlin was versified into two English poems, Of Arthour and of Merlin and Henry Lovelich's Merlin. Its Post-Vulgate version was one of the major sources for Thomas Malory in writing Le Morte d'Arthur.