Frederick William I

(born Aug. 15, 1688, Berlin—died May 31, 1740, Potsdam, Prussia) King of Prussia (1713–40).

The son of Frederick I, he received valuable military experience in the War of the Spanish Succession. Realizing that Prussia's military and financial weakness made it dependent on the relations between the great powers, he built up an army that became a strong military presence on the Continent, instituted economic and financial reforms, centralized his administration, encouraged industry and manufacture, mandated compulsory primary education (1717), and freed the serfs on his own domains (1719). He was succeeded by his son, Frederick II.