Prussia

Prussia emerged from the Teutonic Order's lands on the Baltic. In 1525 Grand Master Albert adopted Lutheranism and secularized the order's remaining Prussian territory as a duchy, held from the Polish crown and governed from Königsberg.

The Hohenzollern electors of Brandenburg inherited the duchy in 1618 and secured sovereignty over it in 1657. In 1701 Frederick I crowned himself King in Prussia; Berlin became the capital of a kingdom that grew into a European power under Frederick the Great, who fought Austria and its allies in the Seven Years' War of 1756–1763.