See biography by A. L. Lowell (1935).
Percival or Perceval is one of King Arthur's legendary Knights of the Round Table. In Welsh literature his name is Peredur (see the Peredur article for that legendary figure). He is most famous for his involvement in the quest for the Holy Grail.
After the death of his father, Percival's mother takes him to the Welsh forests where she raises him ignorant to the ways of men until the age of 15. Eventually, however, a group of knights passes through his wood, and Percival is struck by their heroic bearing. Wanting to be a knight himself, the boy travels to King Arthur's court, and after proving his worthiness as a warrior he is knighted and invited to join the Knights of the Round Table.
Even in the earliest stories he is connected to the Grail Quest. In Chrétien de Troyes' Perceval, le Conte du Graal, he meets the crippled Fisher King and sees the Holy Grail, but he fails to ask the question that would heal the injured king. Upon learning of his mistake he vows to find the Grail castle again and fulfill his quest, as detailed in his part in the Grail legend.
In later accounts, the true Grail hero is Galahad, Lancelot's son. But though his role in the romances had been diminished, Percival remained a major character and was one of only two knights (the other was Sir Bors) who accompanied Galahad to the Grail castle and completed the quest with him.
In early versions, Percival's sweetheart was Blanchefleur and he became the King of Carbonek after healing the Fisher King, but in later versions he was a virgin who died after achieving the Grail. In Wolfram's version, Percival's son is Lohengrin, the Knight of the Swan.
Chrétien wrote the first story of Percival; Wolfram von Eschenbach's Parzival, Sir Thomas Malory's Le Morte d'Arthur, and the nonextant Perceval of Robert de Boron are other famous accounts of his adventures.