From the back of the book:
Charlemagne - Conqueror, statesman, lawmaker, the greatest medieval king of Europe. His reign lasted forty-four years, but his influence was felt for a thousand. From the chaos of the dark ages he forged a kingdom that rivaled Roman Byzantium in its power and prestige. Join the noblest heroes of the age - mighty Rikand, Bradamant the warrior maiden, arch-bishop Turpin, and Malagigi the Wizard - on royal quests and wars against the Lombards, Moors, Saxons, and Vikings. Find adventure at the dawn of chivalry!
This book gives a short survey of Carolingian history, tells you how you adapt AD&D characters to this historical setting, and gives information about the life in this period.
The book also comes with a separate sheet showing a number of maps for the era.