Margraviate of Brandenburg fief of the Polish–Lithuanian Commonwealth, to which the electors paid homage. The electors of Brandenburg spent the next two centuries attempting to gain lands to unite their separate territories (the Mark Brandenburg, the territories in the Rhineland and Westphalia, and Ducal Prussia) to form one geographically contiguous domain. In the Peace of Westphalia ending the Thirty Years' War in 1648, Brandenburg-Prussia acquired Farther Pomerania and made it the Province of Pomerania by the Treaty of Stettin (1653). In the second half of the 17th century, Frederick William, the "Great Elector", developed Brandenburg-Prussia into a major power. The state constructed Brandenburg's
Treaty of Stettin (1653) Pomerania became Brandenburgian Pomerania. During the war, Sweden had occupied the Duchy of Pomerania in 1630. The last Griffin duke Bogislaw XIV died in 1637, his duchy was supposed to be inherited by Brandenburg, who based her claims on in the Treaty of Grimnitz. This however was hindered by the Swedish presence. The 1648 Peace of Westphalia ended the war, and Pomerania was to be partitioned between Brandenburg and Sweden. The 1650 Treaty of Nuremberg roughly defined the areas that should be under control of Sweden and Brandenburg, respectively. The precise border was drawn in the 1653 Treaty of Stettin,