Duchy of Courland and Semigallia

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Duchy of Courland and Semigallia" – news · newspapers · books · scholar · JSTOR (March 2019) (Learn how and when to remove this message)

Duchy of Courland and Semigallia Ducatus Curlandiæ et Semigalliæ (Latin) Kurzemes un Zemgales hercogiste (Latvian) Księstwo Kurlandii i Semigalii (Polish) Kuršo ir Žiemgalos kunigaikštystė (Lithuanian) Herzogtum Kurland und Semgallen (German) Hertigdömet Kurland och Semgallen (Swedish)
1561–1795
Flag Coat of arms
Duchy of Courland and Semigallia in 1714   Duchy of Courland and Semigallia   Polish-Lithuanian Commonwealth
Status	Vassal state of Grand Duchy of Lithuania (1561–1569) and Poland–Lithuania (1569–1795)
Capital	Mitau
Common languages	German Latvian Livonian Latgalian
Religion	Lutheran, Roman Catholic
Demonym(s)	Courlander, Couronian, Courish, Courlandish
Government	Monarchy
Duke
• 1561–1587	Gotthard Kettler (first)
• 1769–1795	Peter von Biron (last)
Legislature	Landtag
History
• Treaty of Vilnius	28 November 1561
• Colonial acquisitions	1637–1690
• Third Partition of Poland	28 March 1795
Area
• Total	27,290 km2 (10,540 sq mi)
Population
• Estimate	~200,000 (1794)
• Density	7.3/km2 (18.9/sq mi)
Currency	Thaler
Preceded by Succeeded by Bishopric of Courland Livonian Order Courland Governorate
Today part of	Latvia

The Duchy of Courland and Semigallia (Latin: Ducatus Curlandiæ et Semigalliæ; German: Herzogtum Kurland und Semgallen; Latvian: Kurzemes un Zemgales hercogiste; Lithuanian: Kuršo ir Žiemgalos kunigaikštystė; Polish: Księstwo Kurlandii i Semigalii) was a duchy in the Baltic region, then known as Livonia, that existed from 1561 to 1569 as a nominally vassal state of the Grand Duchy of Lithuania and subsequently made part of the Crown of the Polish Kingdom from 1569 to 1726^[1] and incorporated into the Polish–Lithuanian Commonwealth in 1726.^[2] On October 24, 1795, it was annexed by the Russian Empire in the Third Partition of Poland.

There was also a short-lived wartime state with the same name that existed from March 8 to September 22, 1918. Plans for it to become part of the United Baltic Duchy, subject to the German Empire, were thwarted by Germany's surrender of the Baltic region at the end of the First World War.^[3] The area became a part of Latvia at the end of World War I.