The aim of this article is to analyse the infrastructural investments made by the Franks to pacify Saxony, and to secure the control of the Elbe River territories. I will mostly use the written sources of the Carolingian era that described, in various forms, the construction of new infrastructures and the conquest of the enemies’. I will also utilize the archaeological data, so as to be able to confirm the accounts of the written sources. Through this analysis I will highlight the central authority’s constant effort to control, protect and rule the newly conquered territories of Saxony and the Elbe.