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
Duchy of Limburg Eighty Years' War, ended by the 1648 Peace of Westphalia. An area known as Limburg of the States, consisting of parts of Overmaas (but no part of the Duchy of Limburg itself), was ceded to the Dutch Republic. In 1661, the Dutch and the Spanish agreed on a re-partition of the county of Dalhem. The duchy of Limburg itself remained undivided under Spanish Habsburg rule as part of the Southern Netherlands, passing to the Austrian Habsburgs under the Treaty of Utrecht in 1713. When the region was occupied by the French in 1794, the Austrian duchy of Limburg proper was