Guilhem first composed in the Occitan language in 1216–1220, during which period he produced the panegyric Pos N'Aimerics a fait mesclança e batailla, a song in which the noble women of Italy put an end to a feud for supremacy at court between Selvaggia and Beatrice di Oramala, daughters of Conrad Malaspina.
He encountered a "trickster" who told him to recite daily the entire Psalter and 150 Paternosters and to give alms to seven poor men before he ate each day, then she would come back to life, but would never eat, drink, or talk.
This bizarre legend is related to a partimen between Guilhem and Sordello, Un amics et un'amia, in which the former posed the dilemma of whether it is better to follow a deceased lover to death or to move on.
Guilhem was a Ghibelline in sympathy and he wrote Un sirventes farai d'una trista persona to attack the Guelph podestà Ponzio Amato di Cremona.
A charter of Ottone del Carretto dated that same month was witnessed by one "Guillelmus de la Turri", possibly the same person as the troubadour.