During the 10th and 11th centuries, Peenemünde was part of the region of Circipania, an area settled by the Circipanes, a West Slavic tribe constituent of the Lutici federation.
First, a Mecklenburgian expedition led by Henry Borwin III of Mecklenburg-Rostock annexed most of Circipania, the western part of the duchy comprising the terrae Gnoien, Altkalen and Demmin, leaving only the residential burgh of Demmin under Wartislaw's control.