Perceval’s maternal uncle in Wolfram’s Parzival. He is unnamed in Chrétien’s Perceval, but he corresponds to the Hermit King of Chrétien’s continuators.
A member of the Grail Family, Trevrizent was the son of Frimutel and the brother of Anfortas, Herzeloyde (Herselojde), Schoysiane, and Repanse de Schoye.
As a youth, he had dozens of adventures in exotic kingdoms. After Anfortas received his debilitating wound, Trevrizent retired to a hermitage at the Fontane la Salvæsche where he lived in humble penance. Perceval encountered him there and Trevrizent served as his tutor, educating him on the ways of the Grail and of God. When Anfortas was healed, Trevrizent returned to the Grail Castle to live out his days.
Source
Parzival | Wolfram von Eschenbach, 1200–1210