Guillem de Cabestany (Catalan pronunciation: [ɡiˈʎɛm də kəβəsˈtaɲ]; 1162–1212) was a Catalan troubadour from Cabestany in the County of Roussillon. He is often known by his Old Occitan name, Guilhem de Cabestaing, Cabestang, Cabestan, or Cabestanh (pronounced IPA: [ɡiˈʎɛm de kabesˈtaɲ]).
Not much reliable info is known about Guillem de Cabestany. He is probably the son of Arnau de Cabestany, a noble of Roussillon, probably a vassal in relation with the lords of Castell Rosselló. Cabestany itself is a fief located immediately next to the east of Castell Rosselló and southwest of Canet (a future viscounty).
He is said to have been fighting with Peter II of Aragon at the Battle of Las Navas de Tolosa against the Almohads in 1212.
According to his legendary vida, he was the lover of Margarida or Seremonda (or Soremonda), wife of Raimon of Castell Rosselló. On discovering this, Raimon fed Cabestany's heart to Seremonda. When he told her what she had eaten, she threw herself from the window to her death. This legend appears later in Giovanni Boccaccio's Decameron and in the Cantos of Ezra Pound. It also inspired the opera Written on Skin by George Benjamin and Martin Crimp, created in 2012. With reference to regional historian Jules Canonge, Cabestany is presented as the archetypal troubador in Ford Madox Ford's book Provence.