THE period that we call the Middle Ages extends from the break-up of the Roman Empire in the west in the fifth century to the Renaissance in the fifteenth – a period of about a thousand years. The night of this great day of human history may be said to last through the first three hundred years (450-7 50), and the early dawn begins, with the events that lead to the establishment of the Empire of Charles the Great. The eleventh and twelfth centuries are the morning, and the thirteenth the high noon, from which it declines to the afternoon of the fourteenth century and the evening of the fifteenth...