The Historia Ecclesiastica
The Historia Ecclesiastica, described as the greatest English social history of the Middle Ages, falls into three sections:
1- Books i and ii, which are historically valueless, give the history of Christianity from the birth of Christ. After 855 this becomes a bare catalogue of popes, ending with the name of Innocent I. These books Orderic added in 1136–1141 as an afterthought to the original scheme.
2- Books iii through vi form a history of St Evroul, the original nucleus of the work. Planned before 1122, they were mainly composed in the years 1123–1131. The fourth and fifth books contain long digressions on the deeds of William the Conqueror in Normandy and England. Before 1067 these are of little value, being chiefly derived from two extant sources: William of Jumieges' Gesta Normannorum Ducum and William of Poitiers' Gesta Guillemi. For the years 1067–1071 Orderic follows the last portion of the Gesta Guillemi, and is therefore of the first importance. From 1071 he begins to be an independent authority. Notices of political events in this part of his work are far less copious than in the later books.
3- Books vii through xiii relegate ecclesiastical affairs to the background. In this section, after sketching the history of France under the Carolingian and early Capet dynasties, Orderic takes up the events of his own times, starting from about 1082. He has much to say concerning the Empire, the papacy, the Normans in Sicily and Apulia, the First Crusade (for which he follows Fulcher of Chartres and Baudri of Bourgueil). But his chief interest is in the histories of the three brothers Robert Curthose, Duke of Normandy, William Rufus and Henry I of England. He continues his work, in the form of annals, up to the defeat and capture of Stephen of England at Lincoln in 1141.
The historian Marjorie Chibnall states that Orderic used now lost pancartes (cartularies or collections of charters) of various Norman monastic houses as sources for his historical writings.
Read more about this topic: Orderic Vitalis