At first, Slavic settlements in Germany were either unfortified, or protected by hill-forts with earthen ramparts and ditches, or naturally protected by the geography of the area, i.e. steep promontories partly surrounded by a river. In the late 8'th century AD, the castrum made its appearance. It was the next step - a more heavily fortified hill-fort (usually 20 to 70 sq. Km., but sometimes up to 150 sq. Km.) on a steep hill and was surrounded by open settlements. It had massive earthen ramparts with built-in wooden reinforcements, and many stones built into the face and core of the walls. When many areas were consolidated, they often formed a castle-district (the next level of settlement).

The populations concentrated in these communities became more and more specialized concerning their labor. Ore-smelters, iron-workers, blacksmiths, potters and jewelers (particularly in Moravia) became respected here. Iron workshops here produced ploughshares, sickles, knives, axes and swords, along with other tools. There were also specialists in leather working, weaving, stone cutting, bone and woodworking and ceramic art. In Lupka, about 250 pots were found with property symbols on them such as crosses, wheels and rectangles. One of these symbols was a swastika - its first appearance, so far as I know.