Belarusian

The Belarusian language, sometimes referred to as White Ruthenian, is the language of the Belarusian people. It is an official language of Belarus, along with Russian, and is spoken abroad, chiefly in Russia, Ukraine, and Poland. Prior to Belarus gaining its independence from the Soviet Union in 1991, the language was known in English as Byelorussian or Belorussian, transliterating the Russian name, белорусский язык, or alternatively as White Ruthenian or White Russian. Following independence, it became known also as Belarusian. Wikipedia