Austorc's only piece, "Ai! Dieus! Per qu'as facha tan gran maleza", was composed after the defeat in 1250 of the Seventh Crusade under Louis IX of France. It was Hermann Schindler who first proposed that the piece referred to the Crusade of 1250 and not that of 1270, on which Louis died. Whatever the Crusade, Kurt Lewent, whose dissertation was the first major study of Occitan Crusading songs, believed that Austorc was a combatant in it. Austorc was surprised that God would allow the Crusade's defeat, but not surprised that Christians would therefore convert to Islam. An excerpt goes like this: