Ademar apparently participated in the war against the Albigensian Crusade, for he was captured by Simon de Montfort on 6 May 1212 and is not heard from again.
On the occasion of his capture he composed a sirventes in imitation of Bertran de Born, Si tot m'ai estat lonjamenz.
His only other extant song is Pons, viscoms, lezir e sojor, a cobla esparsa or cobla de circonstance.
Ademar may also have participated in one of the Crusades (possibly the Fourth or the Reconquista).
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