Katharina Friederike Wilhelmine Benigna, Princess of Courland, Duchess of Sagan ; died 29 November 1839 in Vienna, Austrian Empire) was a German noble from the ruling family of Courland and Semigallia and a Duchess of Sagan. Wilhelmine is mainly known for her relationship with Klemens Metternich, a statesman of the Austrian Empire.

Jelgava is a state city in central Latvia about 41 kilometres southwest of Riga. It is the largest town in the region of Zemgale (Semigalia). Jelgava was the capital of the united Duchy of Courland and Semigallia (1578–1795) and was the administrative center of the Courland Governorate (1795–1918).