Oathbreakers: How the Quarrels of Charlemagne's Heirs Created Medieval Europe

By the beginning of the 9th century, the Frankish king Charlemagne had brought enormous territories under his rule: from the Pyrenees in the west to the Danubian Slavs in the east, from the Danish March in the north to Italy in the south. The Pope crowned him with the imperial title. However, this realm proved short-lived. Even under Charlemagne’s son, Louis the Pious, it began to come apart, and then his sons—Lothair, Charles the Bald, and Louis the German—met in the fierce Battle of Fontenoy and divided their father’s and grandfather’s inheritance into three parts. Thus, the outlines of the political map of medieval Europe took shape.

Some see in the Frankish Empire an attempt to revive Ancient Rome; others view it as a forerunner of the future European Union. What was it truly like, for what reasons did it fall apart, and why did the Carolingian dynasty fade away along with it? These questions are addressed by medieval historians Matthew Gabriel and David M. Perry in their gripping book.