Brandenburg-Prussia

Brandenburg-Prussia
Brandenburg-Preußen
Personal union between the Margraviate of Brandenburg and Duchy of Prussia
1618–1701
Flag
Brandenburg-Prussia within the Holy Roman Empire (1618)
Capital		Berlin and Königsberg
Government		Feudal monarchies in personal union
Elector-Duke
•	1618–1619	John Sigismund
•	1619–1640	George William
•	1640–1688	Frederick William
•	1688–1701	Frederick III (Frederick I)
Historical era		Holy Roman Empire of the German Nation
•	Personal union	August 27, 1618
•	Prussian independence	September 19, 1657
•	Elevation to kingdom	January 18, 1701
Preceded by Succeeded by Margraviate of Brandenburg Duchy of Cleves County of Mark County of Ravensberg Duchy of Prussia Bishopric of Minden Bishopric of Halberstadt Duchy of Pomerania Archbishopric of Magdeburg Lauenburg and Bütow Land Draheim Kingdom of Prussia

Flag

Brandenburg-Prussia (German: Brandenburg-Preußen) is the historiographic denomination for the Early Modern realm of the Brandenburgian Hohenzollerns between 1618 and 1701. Based in the Electorate of Brandenburg, the main branch of the Hohenzollern intermarried with the branch ruling the Duchy of Prussia, and secured succession upon the latter's extinction in the male line in 1618. Another consequence of the intermarriage was the incorporation of the lower Rhenish principalities of Cleves, Mark and Ravensberg after the Treaty of Xanten in 1614. The Thirty Years' War (1618–48) was especially devastating. The Elector changed sides three times, and as a result Protestant and Catholic armies swept the land back and forth, killing, burning, seizing men and taking the food supplies. Upwards of half the population was killed or dislocated. Berlin and the other major cities were in ruins, and recovery took decades.

By the Peace of Westphalia, which ended the Thirty Years' War in 1648, Brandenburg gained Minden and Halberstadt, also the succession in Farther Pomerania (incorporated in 1653) and the Duchy of Magdeburg (incorporated in 1680). With the Treaty of Bromberg (1657), concluded during the Second Northern War, the electors were freed of Polish vassalage for the Duchy of Prussia and gained Lauenburg–Bütow and Draheim. The Treaty of Saint-Germain-en-Laye (1679) expanded Brandenburgian Pomerania to the lower Oder.