Frederick William III was King of Prussia from 16 November 1797 until his death in 1840. He was concurrently Elector of Brandenburg in the Holy Roman Empire until 6 August 1806, when the empire was dissolved.
Frederick William III ruled Prussia... Wikipedia
Born: August 3, 1770, Potsdam, Germany
Died: June 7, 1840 (age 69 years), Berlin, Germany
Children: Frederick William IV of Prussia, William I, Princess Louise of Prussia, and more
Grandchildren: Frederick III, German Emperor, Alexander II of Russia, Grand Duke Konstantin Nikolayevich of Russia, and more
Great grandchildren: Wilhelm II, Alexander III of Russia, Olga Constantinovna of Russia, and more
Spouse: Auguste von Harrach (m. 1824–1840) and Louise of Mecklenburg-Strelitz (m. 1793–1810)