This fourth volume discusses the publishing procedure for secular and religious writings of late antiquity and the factors that led to the impoverishment of the monumental libraries in Rome. New centers of learning grew up in the monasteries, where great libraries containing educational and instructive books and representative works of Christian literature came into being. Monastic libraries were founded throughout Europe, including the regions with Celtic and Anglo-Saxon populations: those at Monte Cassino, Bobbio, St. Gallen, Fulda, Cluny and elsewhere are dealt with extensively. Mention is also made of the libraries founded in universities and of the new philosophy of forming school libraries, as in Bologna and Paris.