The Scheldt boundary, which since 925 AD separated West and East Francia, was already by that time the boundary between the Celtic tribes and the Roman civitates. West Francia rapidly disintegrated, thanks to the increasing feudal powers. From the ninth century onwards it was no longer the Carolingians who were crowned as king but the dukes of Francia. At the same time the power of the counts of Flanders increased.

In the German Empire, in the meantime, the Carolingians had died out and in 919 AD the empire passed into the hands of Henry I (Duke of Saxony). Under his successors Otto I, II and III (until 1002 AD) the Holy Roman Empire was restored here. Emperor Otto the Great (936-973 AD) managed to establish his authority and set up bishops as his tenants; since, in the normal course of events, bishops were not allowed to inherit anything, they formed reliable pillars of support for his authority.

Between 800 and 1100 AD the recognition of a common "German" language grew within the East-Frankish empire. The Franks, who had a dominant position in the empire, had been able to raise their own language to the status of leading language right from the eighth century. The "theodisca lingua" is first mentioned in texts in 788 AD, and was also spoken in the Netherlands.