The number of holy men who originally accompanied St. Philibert to his new abbey, was only seventy; but they increased with surprising rapidity; insomuch, that his successor, St. Aicadras, who received the pastoral staff, after a lapse of little more than thirty years from the foundation of Jumieges, found himself at the head of nine hundred monks, besides fifteen hundred attendants and dependants of various denominations.
During all these early ages, the monastery of Jumieges continued to be accounted one of the most celebrated religious houses in France. Its abbots are repeatedly mentioned in history, as enjoying the confidence of sovereigns, and as charged with important missions. In their number, was Hugh, grandson of Pepin le Bref, or, according to other writers, of Charlemagne. Here also, Tassilo, Duke of Bavaria, and his son, Theodo, were compelled to immure themselves, after the emperor had deposed them; whilst Anstruda, daughter of Tassilo, was doomed to share his imperial bed.
An aera of misfortune began with the arrival of the Normans. It was in May, in the year 841, that these dreadful invaders first penetrated as far as Rouen, marking their track by devastation. On their retreat, which almost immediately succeeded, they set fire to Jumieges, as well as to the capital. In their second invasion, under Ironside and Hastings, the “fury of the Normans” was poured out upon Neustria; and, during their inroad, they levelled Jumieges with the ground. But the monks saved themselves: they dispersed: one fled as far as St. Gall; others found shelter in the royal abbey of St. Denis; the greater part re-assembled in a domain of their own, called Haspres, in Flanders, whither they carried with them the bodies of St. Aicadrus and St. Hugh: there too they resided till the conversion of their enemies to Christianity.