Ostsiedlung
Though settlement had to a lower degree occurred in the Frankish marches already, massive settlement did not start until the 12th century (e.g. in East Holstein, West Mecklenburg, Central and Southeastern marches), and in the early 13th century (e.g. in Pomerania, Rügen), following the reassertion of Saxon authority over Wendish areas (the Holstein area by Holstein Count Adolf II, Brandenburg by Albert the Bear, Mecklenburg and Pomerania by Henry the Lion) in the 1150s). The activities of the Teutonic Order accelerated settlement along the Baltic coast.
During the Ostsiedlung, Germans settled east of the Elbe and Saale rivers, regions largely inhabited by Polabian Slavs. Likewise, in Styria and Carinthia, German communities took form in areas inhabited by Slovenes.
The emigration of inhabitants of the Valais valley in Switzerland to areas that had been settled before by the Romans had to some extent the same preconditions as the colonisation of the East.
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