Gotthard Kettler
Duke of Courland and Semigallia
Reign	28 November 1561 – 17 May 1587
Successor	Friedrich Kettler
Born	2 February 1517 Anröchte, Duchy of Cleves, Holy Roman Empire
Died	17 May 1587(1587-05-17) (aged 70) Mitau, Duchy of Courland and Semigallia
Burial	Ducal crypt in the Jelgava Palace
Spouse	Duchess Anna of Mecklenburg ​ ​ (m. 1566)​
Issue	Anna, Princess Raziwiłł Friedrich, Duke of Semigallia Wilhelm, Duke of Courland
House	Kettler
Father	Gotthard Kettler zu Melrich
Mother	Sophie of Nesselrode
Religion	Lutheranism

Gotthard Kettler, Duke of Courland (also Godert, Ketteler, German: Gotthard Kettler, Herzog von Kurland; 2 February 1517 – 17 May 1587) was the last Master of the Livonian Order and the first Duke of Courland and Semigallia.

Biography

Kettler was born near Anröchte, Kreis Soest, of an old Westphalian noble family and the ninth child of the German knight Gotthard Kettler zu Melrich (mentioned 1527–1556) and his wife Sophie of Nesselrode. Gotthard's older brother Wilhelm Kettler was bishop of Münster from 1553 to 1557.

Kettler enlisted in the Livonian order around 1537 and became a knight. In 1554 Gotthard Kettler became Komtur of Dünaburg (Daugavpils),^[1] and in 1557 Komtur of Fellin (Viljandi). In 1559, during the Livonian War (1558–1582) he succeeded Wilhelm von Fürstenberg as a Master of the Teutonic Order in Livonia. When the Livonian Confederation came under increasing pressure from Ivan IV of Russia, Kettler converted to Lutheranism and secularised Semigallia and Courland. On the basis of the Treaty of Vilnius (28 November 1561), he created the Duchy of Courland and Semigallia as a vassal state of the Grand Duchy of Lithuania, which was soon merged into the Polish–Lithuanian Commonwealth.^[2]

Following the Duke's proposal in 1567, the regional assembly (landtag) decided to build 70 new churches and 8 schools in the remote areas of Duchy where many peasants still lived and died unbaptized.

He died on 17 May 1587 in Mitau (Jelgava), aged 70. His heirs ruled in Courland until 1737.

Family

On 11 March 1566 Kettler married Anna, Duchess of Mecklenburg, daughter of Duke Albert VII of Mecklenburg-Güstrow and Princess Anna of Brandenburg.^[3] The couple had seven children, three of whom died early. His sons Friedrich Kettler and Wilhelm Kettler succeeded him as dukes. The daughter Anna Kettler married the Lithuanian prince Albrecht Radziwiłł, the son of Mikołaj Radziwiłł Czarny, the daughter Elisabeth Kettler married the Adam Wenceslaus, Duke of Cieszyn of Duchy of Teschen.