As the king since 1713 Frederick William I modernised the administration and economy and reorganised the ailing financial situation caused by the ostentatious court maintained by his father. He gave the country an inner structure and had a long-term influence on it.
Despite strict fiscal austerity, the "Soldier King" doubled his army thus securing the independence of his kingdom where military matters enjoyed priority over all civilian ones ever since. He was pious but was considered despotic, led a simple life and worked hard. Court life, art and science meant little to him, but he loved hunting.
In later East Prussia he distinguished himself above everybody else in the reconstruction of the country, which had been devastated and partly depopulated after war and epidemics.
It was there that he disciplined the nobility through cadet training, i.e. officer training from childhood. He also banned military service abroad. The size of aristocratic estates was reassessed, their taxes redefined. For the first time domains, i.e. royal estates, were leased to the bourgeoisie.
Illustrations:
1.) Georg Wenzeslaus von Knobelsdorff (1699-1753): Frederick William I, around 1737
The "Soldier King" had portraits of himself painted in a completely different manner from that of his father: standing as a soldier with a breastplate, boots and in the simple uniform of a colonel. In his hand the king is holding a marshal's baton as a symbol of his military command but no sceptre. Instead of the crown or a full-bottomed wig the "Soldier King" is wearing only a short one that was customary in the military.
2.) Edict of Frederick William I in 1724, here for the regulation of game imports into the city. The king himself regulated the procedures of his administration and the daily life of his citizens down to the last detail with numerous decrees. The "Prussian Order" was essentially his doing.