Latvian language
Upper Latvian dialect is spoken in Eastern Latvia. It is set apart from rest of the Latvian by number of phonetic differences. The dialect has two main varieties – Selonian and Non-Selonian. There is a standard language, the Latgalian language, which is based on deep Non-Selonian varieties spoken in south of Latgale. The term "Latgalian" is sometimes also applied to all Non-Selonian varieties or even the whole dialect. However, it is unclear if it is accurate to use the term for any varieties besides the standard language. While the term may refer to varieties spoken in Latgale or by Latgalians, not all speakers identify as speaking Latgalian, for example, speakers of deep Non-Selonian varieties in Vidzeme explicitly deny speaking Latgalian.
Demographic history of the Vilnius region
The city of Vilnius, now the capital of Lithuania, and its surrounding region have at various times come under Polish-Lithuanian, Russian, Polish, German, and Soviet rule. The population has been categorised by linguistic and sometimes also religious indicators. At the end of the 19th century the main languages spoken were Polish, Lithuanian, Belarusian and Russian. Both Catholic and Orthodox Christianity were represented, while a large proportion of those within the city were Jews. The "Lithuanian" element was seen as declining, while the "Slavic" element was increasing.