He was the eldest son of a French priest, Odeler of Orleans, who had entered the service of Roger of Montgomery, 1st Earl of Shrewsbury, and had received from his patron a chapel in that city. When Orderic was five, his parents sent him from an English priest, Siward by name, who kept a school in the church of SS Peter and Paul at Shrewsbury. At the age of eleven he was entered as a novice in the Norman monastery of St Evroul-en-Ouche, which Earl Roger had formerly persecuted but, in his later years, was loading with gifts. The parents paid thirty marks for their son's admission; and he expresses the conviction that they imposed this exile upon him from an earnest desire for his welfare. Odeler's respect for the monastic profession is attested by his own retirement, a few years later, into a religious house which Earl Roger had founded at his persuasion. But the young Orderic felt for some time, as he tells us, like Joseph in a strange land. He did not know a word of French when he reached Normandy; his book, though written many years later, shows that he never lost his English cast of mind or his attachment to the country of his birth.
His monastic superiors rechristened him Vitalis (after a member of the legendary Theban Legion) because they found a difficulty in pronouncing his baptismal name. But, in the title of his great chronicle he prefixes the old to the new name and proudly adds the epithet Angligena.
His cloistered life was uneventful. He became a deacon in 1093, and a priest in 1107. He left his cloister on several occasions, and speaks of having visited Croyland, Worcester, Cambrai (1105) and Cluny (1132). But he turned his attention at an early date to literature, and for many years he appears to have spent his summers in the scriptorium.
His superiors (at some time between 1099 and 1122) ordered him to write the history of St Evroul. The work, the Historia Ecclesiastica (Ecclesiastical History), grew under his hands until it became a general history of his own age. St Evroul was a house of wealth and distinction. War-worn knights chose it as a resting-place of their last years. It was constantly entertaining visitors from southern Italy, where it had planted colonies of monks, and from England, where it had extensive possessions. Thus Orderic, though he witnessed no great events, was often well-informed about them. In spite of a cumbrous and affected style, he is a vivid narrator; and his character sketches are admirable as summaries of current estimates. His narrative is badly arranged and full of unexpected digressions. But he gives us much invaluable information for which we should search the more methodical chroniclers in vain. He throws a flood of light upon the manners and ideas of his own age; he sometimes comments with surprising shrewdness upon the broader aspects and tendencies of history. His narrative breaks off in the middle of 1141, though he added some finishing touches in 1142. He tells us that he was then old and infirm. Probably he did not long survive the completion of his great work.
The Historia Ecclestiastica 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 were added, as an afterthought, to the original scheme; they were composed in the years 1136-1141.
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' Historia Normannorum 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. But his notices of political events in this part of his work are far less copious than in the later books.
3- Books vii through xiii, where ecclesiastical affairs are relegated to the background. In this section, after sketching the history of France under the Carolingians and early Capets, 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 Duke Robert 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.