Christianization of Pomerania

Medieval Pomerania was converted from Slavic paganism to Christianity by Otto von Bamberg in 1124 and 1128 (Duchy of Pomerania), and in 1168 by Absalon (Principality of Rügen).

Earlier attempts at Christianization, undertaken since the 10th century, failed or were short-lived. The new religion stabilized when the Pomeranian dukes founded several monasteries and called in Christian, primarily German settlers during the Ostsiedlung. The first Pomeranian abbey was founded in 1153 at the site where the first Christian duke of Pomerania, Wartislaw I, was slain by a pagan. The Duchy of Pomerania was organized by the Roman Catholic Church in the Bishopric of Cammin in 1140. Pomeranian areas not belonging to the duchy at this time were attached to the dioceses of Włocławek (East), Roskilde (Rügen) and Schwerin (West).

When the Bishopric of Havelberg was founded in 948, the constitution document mentions the area between Peene and Oder among the bishopric's belongings. In 983, the Holy Roman Empire lost control over the region due to a Slavic uprising.

The first Polish duke Mieszko I invaded Pomerania and subdued the gard of Kołobrzeg (Kolberg) and the adjacent areas in the 960s. He also fought the Wolinians, but despite a won battle in 967, he did not succeed in the town of Wolin itself. His son and successor Boleslaw I continued to campaign in Pomerania, but also failed to subdue the Wolinians and the lower Oder areas.

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