Did you mean: Guilhem de Saint-Didier
Guilhem de Saint-Leidier, also spelled Guilhem de Saint Deslier, Guillem de Saint Deidier and Guilhèm de Sant Leidier was a troubadour of the 12th century, composing in Occitan. He was lord of Saint-Didier-en-Velay, was born at some date before... Wikipedia