Sēlija

Selonia (Latvian: Sēlija; Lithuanian: Sėla), also known as Augšzeme (the "Highland"), is a cultural region of Latvia encompassing the eastern part of the historical region of Semigallia (Latvian: Zemgale). Its main city and cultural center is Jēkabpils. The Selonian language has become extinct, though some of the inhabitants still speak a Latgalian dialect.

Not an administrative division in modern Latvia, Selonia currently contains the municipalities of Aknīste, Ilūkste, Jaunjelgava, Jēkabpils, Nereta, Sala, and Viesīte, plus the parts of the city of Daugavpils, city of Jēkabpils, Daugavpils municipality and Krāslava municipality on the left bank of the Daugava River.

The subjugation and baptism of the Selonians started in 1208, when Albert of Buxhoeveden captured Sēlpils (Latin: castrum Selonum). The term "Selonians" is most probably the German adaptation of the Livonian name "Highlanders", which leads to the hypothesis that the Selonians and Aukštaitians belonged to the same ethnos. The Livonian Chronicle of Henry describes the Selonians as allies of the Lithuanians. In 1218 the region formed a Selonian diocese, but in 1226 part of that diocese was joined to the Riga archbishopric and the Bishopric of Semigalia was formed. Nowadays the region is mainly inhabited by Latvians with larger proportion of ethnic minorities of Russians, Poles, Belarusians and Lithuanians in the southeastern municipalities (Ilūkste Municipality and Daugavpils Municipality).