Frederick William of Brandenburg

Timeline

1. 1620–1640Berlin · BrandenburgBorn near Zerndorf, he experienced the turmoil of the Thirty Years' War from childhood; he studied in the Dutch Republic, influenced by Calvinism and Dutch military-financial models. He succeeded as Elector of Brandenburg in 1640 after his father George William's death.
2. 1640–1660Königsberg · East PrussiaHe rebuilt towns and armies after the war and instituted a tribute system to maintain a standing army; during the First Northern War (1655–1660) he maneuvered between Sweden, Poland, and the Empire, allied with Sweden after the Battle of Warsaw in 1657 to gain full sovereignty over East Prussia, confirmed by the Treaty of Oliva in 1660.
3. 1661–1670Berlin · BrandenburgIn 1661 he established a territorial chamber (Amtskammer) in Prussia to integrate taxation and administration; in 1666 his rights over Cleves, Jülich, and Ravensberg were formally recognized; in 1667 he introduced an excise tax in Brandenburg to bypass the nobility estates' fiscal veto and suppressed separatist forces in East Prussia. Diplomatically he largely maintained neutrality, accumulating strength for later wars against France, the Dutch, and Sweden.
4. 1670–1688Potsdam · BrandenburgFrom 1672 he intervened in the Franco-Dutch War, crushing the Swedish army at the Battle of Fehrbellin in 1675 and briefly recovering large parts of Pomerania; though forced to return some conquests in the Treaty of Saint-Germain-en-Laye in 1679, his military reforms and centralizing model shaped Prussia's rise. He died at Potsdam in 1688.