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.
Latgalians (modern)
During the first independence of Latvia (1918–1940), Latgale was the only region of Latvia with strong regional political parties. Although Latvian governments mainly promoted a united Latvian culture, fostering assimilation of Latgalians, especially after the coup by Kārlis Ulmanis in 1934, the Latgalian language was also used. Books were published in Latgalian, it was taught in some schools, and people could choose to use Latgalian when communicating with the government. They were classified as a Narodnosti in the First All Union Census of the Soviet Union in 1926. In the Nazi German "Generalplan Ost", as far as can be told from the surviving documentation, the Latgalians were scheduled for deportation, while only half of the Latvian population was to be treated so. The reasons for this difference are unclear, but possibly based on racist linguistic arguments, considering that the Nazis planned to physically remove 85% of the Lithuanians (whose language – and by erroneous inference ethnicity – has similarities to Latgalian).