Duchy of Courland and Semigallia
House of Kettler
1561–1737House of Biron
1737–1740House of Brunswick-Bevern
Louis Ernest of Brunswick-Lüneburg
1741House of Wettin
Charles of Saxony
1758–1763House of Biron
1763–1795House of Romanov
1795-1918
Conquered by Russia