Orderic was born on 16 February 1075 in Atcham, Shropshire, England, the eldest son of a French priest, Odelerius of Orléans, who had entered the service of Roger de Montgomerie, 1st Earl of Shrewsbury, and had received from his patron a chapel there. Orderic was one of the few monks who were of mixed parentage as his mother was of English heritage. When Orderic was five, his parents sent him to an English monk, Siward by name, who kept a school in the Abbey of SS Peter and Paul at Shrewsbury.
At the age of eleven, Orderic was entrusted as an oblate to the Abbey of Saint-Evroul in the Duchy of Normandy, which Montgomerie had formerly despoiled but, in his later years, was loading with gifts. The parents paid thirty marks for their son's admission; he expresses the conviction that they imposed this exile upon him from an earnest desire for his welfare. Odeler's respect for the monastic life is attested to by his own entry, a few years later, into a monastery which the earl had founded at his persuasion. Orderic, on the other hand, felt for some time, as he asserts, 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.
When Orderic reached the legal age for profession as a monk, his monastic superiors gave him the religious name of "Vitalis" (after a member of the legendary Theban Legion of Christian martyrs) because they found a difficulty in pronouncing his unusual baptismal name. In the title of his great chronicle, he prefixes the old to the new name and proudly adds the epithet Angligena ("English-born").
Orderic's cloistered life was uneventful. He became a deacon in 1093, and a priest in 1107. He left his cloister on several occasions, speaking of having visited Croyland, Worcester, Cambrai (1105) and Cluny Abbey (1132). He turned his attention at an early date to literature, and for many years appears to have spent his summers in the scriptorium.
Orderic's first literary efforts were a continuation of William of Jumièges' Gesta normannorum ducum, a broad history of the Normans and their dukes from the founding of Normandy, which Orderic carried forward into the early twelfth century.