The area over which the 'west Frankish' kings exercised meaningful authority contracted during the tenth century and new units of power emerged. These have customarily been termed 'territorial principalities' since the publication of Jan Dhondt's important book. Modern French historiography nevertheless remains undecided on the extent of continuity from the Carolingian period. The notion of the northern principalities as 'un prolongement carolingien' is deeply embedded in modern discussions. The principality of Flanders certainly evolved directly out of arrangements made during the reign of Charles the Bald, but its final shape was the result of the military achievements of its rulers. The beginnings of the principality of Blois Chartres Tours are similar. The Historia Normannorum of Dudo of Saint-Quentin, commissioned in the late tenth century for the Norman counts Duke Richard I and II, is the first instance of 'history' written to present a version of a principality's history.