Over the centuries, Koszalin alternated religion and commerce. The early Dzierzecinka River settlement conquered in 1107 by a Piast king became part of the Polish nation, and continued over the next few centuries to house and feed the visitors to the nearby religious site in the Chelmska Mountains.
It became a pilgrimage site in its own right when a chapel was constructed in the 13th century, and later a town when the local property holder Bishop Herman von Gleichen granted civil rights on 23 May 1266.
The Bishops of Koszalin were also its rulers, and that princely line continued to govern the city until it was incorporated by the Brandenburgs. But before that happened, Koszalin made a shrewd purchase that eventually established it as a major trading town that went on to membership in the Hanseatic League. In the middle of the 14th century, the city council agreed to purchase nearby Lake Jamno and with it access to the sea. Koszalin began exporting
agricultural and forest products to Scandinavian countries, Gdansk and Lubeka.
Koszalin continued to strengthen, capping its prestigious position in the 16th and 17th centuries with the usual symbol of power: a castle built by the Bishop princes of the Gryfit Dynasty. It also served as a gathering point for the local assemblies, adding a political feather to its commercial cap.
Control of Koszalin changed hands after the Thirty Years War when together with the West Pomeranian region it became a part of Brandenburg and then Prussia.
In the 18th century, Koszalin again boomed economically by supplying the ever-busy Prussian army with cloth, soap, paper, leather products, and coaches. Its industrial role continued up to the present century, but signs of its long prosperity were destroyed by a 18th century fire, and then the 20th century WWII. After the war, it re-entered Polish hands and then revived its religious past when it became a seat of the Koszalin-Kolobrzeg Diocese.
original text courtesy of Koszalin Department of Promotions. Modifications by Internet Polska