Ferdinand Kettler

Ferdinand Kettler (1655 – May 4, 1737) was Duke of Courland and Semigallia from 1730 to 1737. Ferdinand was the son of Jacob Kettler and Louise Charlotte of Brandenburg. Married in 1730 to Johanna Magdalene of Saxe-Weissenfels (1708–1760).

Biography
Ferdinand Kettler was born in November 1, 1655 in Jelgava. From 1658–1660 he, together with whole family, was held captive by the Swedes in Riga and later in Ivangorod.

After his father's death in 1682 duchy passed to his older brother Friedrich Casimir, but Ferdinand was in the polish army where he reached the rank of the lieutenant-general. He participated in battles against Ottoman empire. After Friedrich Casimir died in 1698, his widow together with Ferdinand became guardians of the minor Friedrich Wilhelm and ruled duchy in his name as regents.

When Great Northern War started in 1700, Ferdinand Kettler was involved in battles near Riga. After defeat in the Battle of Daugava he fled to Danzig where he stayed until his death. Council of the duchy (landtag) under Swedish occupation refused to recognize Ferdinand as duke.

When after the wedding with Anna of Russia suddenly died young Friedrich Wilhelm last candidate to the throne from House of Kettler was Ferdinand. However he hesitated to return to Courland. Duchy was ruled by Anna of Russia who acted as a regent. In 1725 Council of Duchy elected Maurice de Saxe as the new duke. However he soon was forced to left Courland after friction with Russian imperial administration.

In 1730 Ferdinand Kettler, then 75 years old, married young Johanna Magdalene of Saxe-Weissenfels. In the same year Anna of Russia became tsarina of Russian empire and Council of Duchy finally recognized Ferdinand as a duke. In 1736 king of Poland August III secretly offered throne of Courland to Ernst Johann Biron who was lover of tsarina Anna and had great influence on state affairs.

Ferdinand Kettler died in Danzig in 4.May 1737. He had no children. Only a month later Council of the Duchy elected Ernst Johan Biron as the new duke.