Amatus of Montecassino (Amatus Casinensis), a Benedictine monk at the Abbey of Montecassino is one of three Italo-Norman chroniclers, the others being William of Apulia and Goffredo Malaterra. His History of the Normans (L'Ystoire de li Normant) in eight books, originally written in Latin ca 1080, but preserved only in a later Old French version, is a prime source for retrieving the history of the Normans in the Mediterranean, as seen from the perspective of the great Abbey, which was one of the most important cultural and religious centers of 11th-century Christendom. Amatus describes the Norman sieges of Bari and Salerno, the conquest of Sicily, and the career of Robert Guiscard, as well as the Gregorian Reforms seen from the papal point-of-view, interspersed with reports of miracles and prophecies.
Many details of 11th-century history, such as the arrow in the eye that killed Harold at the battle of Hastings[1], owe their origin to the chronicler of Montecassino.
The historical novel by Gabriella Brooke, The Words of Bernfrieda: A Chronicle of Hauteville (Cheney: Eastern Washington University Press, 1999) tells of the lady Fredesenda of Hauteville, mother of Robert Guiscard, as seen by her handmaid, who has met Amatus and intends to record "all that Amatus' chronicle will leave out".