 Swantibor and Barnim divided their part of the duchy among themselves in 1435, with Swantibor receiving the island of Rügen and city of Stralsund and the Barnim receiving mainland part except Stralsund.When Swantibor died in 1440, Rügen and Stralsund fell back to Barnim.In 1441, Barnim conquered the Zingst peninsula from the Cistercian St. Nicholas Abbey at Hiddensee.