Who wrote the unfinished Arthurian romance Perceval, le Conte du Graal, the earliest major Grail story?

Chrétien de Troyes wrote Perceval, le Conte du Graal, the earliest major Grail story.

Chrétien composed the romance in Old French during the late 12th century, probably for his patron Philip, Count of Flanders. The poem follows Perceval, a young Welsh knight whose encounters with a mysterious procession include a bleeding lance and a richly decorated grail.

The work is unfinished, so Chrétien never explains exactly what the Grail is or completes Perceval’s spiritual development. Later writers supplied Christian interpretations and expanded the story into prose cycles.

The title is often translated as Perceval, the Story of the Grail. It should not be confused with Wolfram von Eschenbach’s later German poem Parzival, which develops a much fuller Grail mythology.