The Belarusian language, or Belorussian is the language of the Belarusian people and is spoken in Belarus and abroad, chiefly in Russia, Ukraine, and Poland. Prior to Belarus gaining its independence from the Soviet Union in 1992, the language was called "Byelorussian" or "Belorussian" (in accordance with the ethnicity and country names: Byelorussians, Byelorussia, the latter being a transliteration from the Russian language). It belongs to the group of the East Slavonic languages, and shares many grammatical and lexical features with other members of the group. Its predecessor was the Old Belarusian language (up to the 19th cent., conventionally). In Belarus, the Belarusian language is declared as a "language spoken at home" by about 3,686,000 people (36.7% of the population) as of 1999. By less strict criteria, about 6,984,000 (85.6%) of Belarusians declare it their "mother tongue". Other sources put down the "population of the language" as 6,715,000 in Belarus and 9,081,102 in all countries. The Belarusian language is the official language of Belarus, along with Russian.

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