The grandsons of Charlemagne slide into civil war, with thousands of Franks killing each other over the division of the empire.  Though the Treaty of Verdun ends the bloodletting, Frankish troubles are far from over.  Vikings sail up the Seine and sack Paris, finally leaving after being bought off by King Charles of West Francia.  However Louis the German, King of East Francia, makes Viking raiders return what they stole from his territory, and collects tribute money from them.  He may have been particularly disgruntled since his wife took a vow of chastity.  This is the story of a king dubbed "Louis of the Iron Hands" for his extraordinary strength, and the distinctive culture he created in the lands that would become Germany.