century, and this may represent the origin of their name. During their wars with the Frankish empire, the Saxons were described as living north of the Thuringians, as far east as the Elbe. By the time of the Carolingians, most of the North Sea coast between the Rhine and Elbe was inhabited not by the Saxons, but by the medieval Frisians, who were seen as distinct from the Saxons.

Apart from the Frisian coastal area, the Duchy which