between the city of Koszalin and the Pomeranian duke Bogislaw X broke out, resulting in the kidnapping and temporary imprisonment of the duke in Koszalin. Modern Age As a result of German colonization, the town became mostly German-speaking, putting indigenous Slavic speakers at disadvantage. In 1516 local Germans enforced a ban on buying goods from Slavic speakers. It was also forbidden to accept native Slavs to craft guilds, which indicates ethnic discrimination. In 1531 riots took place between supporters and opponents of the Protestant Reformation. In 1534 the city became mostly Lutheran under the influence of Johannes Bugenhagen. In 1568, John Frederick, Duke of Pomerania and bishop of Cammin, started constructing a residence, finished by his successor Casimir VI of Pomerania in 1582. After the 1637 death of the last Pomeranian duke, Bogislaw XIV, the city passed to his cousin, Bishop Ernst Bogislaw von Croÿ of Kammin. Occupied by Swedish troops during the Thirty Years' War in 1637, some of the city's inhabitants sought refuge in nearby Poland. The city was granted to Brandenburg-Prussia after the Treaty of Westphalia (1648) and the Treaty of Stettin (1653), and with all of Farther Pomerania became part of the Brandenburgian Pomerania. Now renamed Cöslin as part of the Kingdom of Prussia, the city was heavily damaged by a fire in 1718, but was rebuilt in the following years. In 1764 on the Chełmska Hill, now located within the city limits, a Pole Jan Gelczewski founded a paper mill that supplied numerous city offices. The city was occupied by French troops in 1807 after the War of the Fourth Coalition. Following the Napoleonic wars, it became the capital of Fürstenthum District (county) and Regierungsbezirk Cöslin (government region) within the Province of Pomerania. The Fürstenthum District was dissolved on 1 September 1872 and replaced with the Cöslin District on December 13. Between 1829 and 1845, a road connecting Cöslin (Koszalin) with Stettin (Szczecin) and Danzig (Gdańsk) was built. Part of this road, from Cöslin (Koszalin) to the nearby town of Sianów, was built in 1833 by around one hundred former Polish insurgents. The town became part of the German Empire in 1871 during the unification of Germany. The railroad from Stettin (Szczecin) through Cöslin (Koszalin) and Stolp (Słupsk) to Danzig (Gdańsk) was constructed from 1858 to 1878. A military cadet school created by Frederick the Great in 1776 was moved from Kulm (Chełmno) to the