Elector Frederick III (1657-1713) became "King in Prussia" due to his elevation as Frederick I, thus taking the decisive step in the unification of his dominion both externally and internally. In the following decades "Prussia" was established as the name of the entire kingdom.
The road to the royal crown was diplomatically difficult, as the emperor did not accept such elevation within the empire. Frederick exploited the dispute over the vacant Spanish throne to obtain imperial approval by way of money payments and support for the imperial troops. Poland also agreed, as Frederick had supported the election of the Saxon Elector August as King of Poland.
His self-crowning took place with great pomp on 18th January 1701 with the Berlin court having moved to Königsberg with 300 wagons. Frederick loved representation and maintained an expensive royal household. His state suffered from taxes, debts and the plague, to which about one third of the population in the region of what was later East Prussia fell victim.
Illustration:
Antoine Pesne (1683-1757) – portrait of Frederick I as King in Prussia on the throne
On this undated portrait Frederick proudly presents the insignia of his newly acquired power. Sitting on the throne in his ermine coat he is holding a golden sceptre in his hand and a golden crown adorned with diamonds with the Prussian blue orb of the empire, adorned with rubies, is on a table next to him. Frederick attached great importance to appropriate representation and made Berlin into a Baroque royal residence with the recently rebuilt city palace by Andreas Schlüter or Charlottenburg palace, where the original of the painting hangs.