Frederick William, Duke of Courland
Appearance
Frederick III Wilhelm von Kettler (19 July 1692 - 21 January 1711) was Duke of Courland and Semigallia from 1698 to 1711. Frederick Wilhelm was the son of Frederick Casimir Kettler and in 1710 he married Anna, daughter of the Tsar Ivan V of Russia. After his death, the Duchy passed in the hands of Russia . It was restored to independence in 1730, when it passed to the lover of Tsarina Anna, Ernst Johann Biron.