Pomeranian Diocese (1140)
On Otto of Bamberg's behalf, a diocese was founded with the see in Wollin (Julin, Jumne, Vineta), a major Slavic and Viking town in the Oder estituary. On October 14, 1140, Adalbert of Pomerania was made the first Bishop by Pope Innocent II. Otto however had died the year before. There was a rivalry between Otto's Diocese of Bamberg, the Diocese of Magdeburg and the Diocese of Gniezno for the incorporation of Pomerania. Pope Innocence II solved the dispute by repelling their claims and placed the new diocese directly under his Holy See. The see of the diocese was the church of St Adalbert in Wollin. The diocese had no clear-cut borders in the beginning, but roughly reached from the Tribsees burgh in the West to the Łeba River in the East. In the South, it comprised the northern parts of Uckermark and Neumark. As such, it was shaped after the territory held by Ratibor I, Duke of Pomerania.
After ongoing Danish raids, Wollin was destroyed, and the see of the diocese was shifted across the Dziwna to Kamień Pomorski's St John's church in 1176. This was confirmed by the pope in 1186. In the early 13th century, the Cammin diocese along with the Pomeranian dukes gained control over Circipania. Also, the bishops managed to gain direct control over a territory around Kolobrzeg and Koszalin.
The Pomerelian areas were integrated into the Kuyavian Diocese of Włocławek.
Read more about this topic: Pomerania During The High Middle Ages