Les Chétifs is an episode in the twelfth century Crusade Cycle describing the fictitious adventures of a group of prisoners captured during the First Crusade. The present edition is based on all the known verse manuscripts, one manuscript in prose and a medieval Spanish translation. These versions have been compared in an analysis of the manuscript tradition and in detailed notes on the text. The edition itself has been laid out with the base text on one page, ard the variants on the facing page, whilst the prose version has been edited separately in an appendix. The texts have been provided with paleographic and literary notes, a full Table of Proper Names and a selective glossary. A full description of each manuscript is followed by an examination of a few facts preserved concerning some further manuscripts now lost. In the introduction all the major problems regarding the origins and development of the branch have been re-examined. The extant poem can be divided into three distinct episodes, each dominated by a different "Chétif". In the first, Richard de Chaumont fights a judicial duel on behalf of Corbaran, the captor of the prisoners, thereby securing their release. The second section sees Baudouin de Beauvais ridding the country of a terrible dragon, while in the third, Harpin de Bourges rescues Corbaran's nephew from a series of abductions. We have shown how the second of these episodes was interpolated after the composition of the other two. It has been claimed by many that Les Chétifs was written entirely, or mainly, in the orient. It is the contention of this thesis that this claim is unjustified and that the branch was composed in North Eastern France. Our refutation of the theory of oriental composition begins with a study of the provenance of the heroes, which illustrates how the original tale did indeed recount a real captivity, but that of a party of pilgrims from Fécamp, in Normandy, to Jerusalem, well before the First Crusade, The tale commemorating this event, long since lost, was to be incorporated, along with distant reminisceneas of the "Arrière-croisade" of 1101, into an early Cycle of the Crusade, which was later cast into a new cycle by Graindor de Douai in about 1190. Despite the oriental appearance of these original first and third episodes, it is certain that both were composed in Prance and based on medieval feudal and folk themes. Nevertheless there was no doubt a conscious effort on the part of successive authors and remanieurs to colour their work with genuine details of oriental life. The poem also includes certain topographical features of Syria and the Holy Land, but the overall impression is that they are vague and were probably borrowed from the Chanson d' Antioche and the Chanson de Jérusalem. In the early thirteenth century the cycle was subject to a further revision (probably at the time when the originally independent Swan-knight Cycle was affixed to it), and the episode of Baudouin de Beauvais and the dragon, which is of Armenian origin, was interpolated into it. It is this remaniement (and not that of Graindor de Douai, as has been hitherto supposed) that has survived and which is given in this edition. The general conclusion is that the branch of Les Chétifs was composed in various stages in Northern Prance. The language of the poet and that of most of the scribes localises the extant version to Picardy. The combined Swan-knight and Crusade Cycles, including Les Chétifs, were later abridged into a prose version, translated into Spanish and were recast into a final reworking known as the Second Cycle of the Crusade, in the mid-fourteenth century. The relationship between these three versions and the original verse redaction is the subject of one chapter, whilst another examines the extent to which Les Chétifs has left any influence on other works of the period.