The Song of the Cathar Wars is the first translation into English of the Old Provençal Canso recounting the events of the years 1204-1218 in Southern France. In an effort to extirpate the Cathar heresy, Pope Innocent III launched what is now known as the Albigensian Crusade, but it was fiercely resisted by the lords and people of the Languedoc, if in the end in vain. This ’song’ was written in two parts, the first by William of Tudela, a supporter of the crusade; the second by an anonymous continuer, wholeheartedly in sympathy with the southerners, although not with the heretics themselves. It stands as a historical source of great importance, not least because it depicts the side that lost. The poem is also a skilful, dramatic and often impassioned composition, evoking the brilliant world of landed knights and the glories and bloody realities of battle. Janet Shirley is an award-winning translator of works on the French Middle Ages. Other publications by her include the Song of Roland and, in this Crusade Texts in Translation series, Crusader Syria in the 13th Century and, with Peter Edbury, Guillaume de Machaut: The Conquest of Alexandria.