Courland is one of the Historical Latvian Lands in western Latvia. The name probably derives from kur̃t, from kwer- (to do, to build). Courland's largest city is Liepāja, which is the third largest city in Latvia. The regions of Semigallia and Selonia are sometimes considered as part of Courland as they were formerly held by the same duke.
Situated in western Latvia, Courland roughly corresponds to the former Latvian districts of Kuldīga, Liepāja, Saldus, Talsi, Tukums and Ventspils.
When combined with Semigallia and Selonia, Courland's northeastern boundary is the Daugava, which separates it from the regions of Latgale and Vidzeme. To the north, Courland's coast lies along the Gulf of Riga. On the west it is bordered by the Baltic Sea, and on the south by Lithuania. It lies between 55° 45′ and 57° 45′ North and 21° and 27° East.
The name is also found in the Curonian Spit and Lithuanian Karšuvos giria - the Courland wood.
The area comprises , of which is made up of lakes. The landscape generally has a low and undulating character, with flat and marshy coastlands. The interior features wooded dunes, covered with pine, spruce, birch, and oak, with swamps and lakes, and fertile patches between. Courland's elevation never rises more than above sea level.
The Jelgava plain divides Courland into two parts, the western side, which is fertile and densely inhabited, except in the north, and the eastern side, less fertile and thinly inhabited.
Nearly one hundred rivers drain Courland, but only three of these rivers – the Daugava, the Lielupe and the Venta – are navigable. They all flow northwestward and discharge into the Baltic Sea.
Owing to its numerous lakes and marshes, Courland has a damp, often foggy, and changeable climate; its winters are severe.
In ancient times the Curonians, a pagan tribe, inhabited Courland. The Brethren of the Sword, a German Catholic military order, subdued the Curonians and converted them to Christianity in the first quarter of the 13th century.