Frederick-William I (1688-1740), King of Prussia 1717-1740. Notorious for his Tabaks-Kollegium and his collection of Lange Kerls (his personal regiment consisting of giant-like soldiers), he was nevertheless a most intelligent politician whose military, financial and administrative reforms created an important basis for the success of his son Frederick the Great.
Johann Harper arrived in Berlin in 1712 and was styled Hof-Kabinettmaler in 1716. For further information on Harper, see: Boo von Malmberg, "Johan Harper", Konsthistorisk Tidskrift, vol. XXIII, nr 3-4, Stockholm 1954/1955, pp. 86-89.