This map depicts the expansion of the territory of the Electors of Brandenburg from the Hohenzollern dynasty, who rose to hold the title “King in Prussia” in 1701. Until the sixteenth century, their territory comprised only the Margraviate of Brandenburg, but in 1618 they inherited the title of ruler over the Duchy of Prussia, which lay outside the Holy Roman Empire. The expanded territory of the Hohenzollerns is therefore referred to as Brandenburg-Prussia, particularly for the period from 1618 to 1701. Even before the Thirty Years’ War, the Hohenzollern margraves succeeded in enlarging their territory through a clever marriage policy. In the Peace of Westphalia, Brandenburg-Prussia acquired East Pomerania and the Principality of Minden as well as the entitlement to the Archbishopric of Magdeburg (acquired in 1680). As the map shows, however, many of these territories were isolated from one another, making a unified political and economic administration very difficult. After the annexation of Silesia (1763), which Frederick II had forced through the Silesian Wars, Prussia became one of the major European powers. The First Partition of Poland in 1772 made West Prussia and the diocese of Warmia Prussian territory, so that there was now a land connection between the heartland of Brandenburg and Prussia. In the course of the Second Partition of Poland, Prussia gained control over the cities of Danzig and Thorn as well as the new province of South Prussia (1793). The Third Partition of Poland in 1795 then awarded Prussia those territories of Poland that were incorporated into the kingdom as the provinces of New East Prussia and New Silesia.