Kirill Trofimovich Mazurov was a Soviet partisan, politician, and one of the leaders of the Belarusian resistance during World War II who governed the Byelorussian Soviet Socialist Republic as First Secretary of the Communist Party of Byelorussia from 1956 until 1965, when he became a member of the Politburo of the CPSU.
Mazurov in 1972
Belarusian is an East Slavic language. It is one of the two official languages in Belarus, alongside Russian. Additionally, it is spoken in some parts of Russia, Lithuania, Latvia, Poland, and Ukraine by Belarusian minorities in those countries.
The Casimir's Code of 1468, in Ruthenian
The third Lithuanian statute of 1588, all three written in Ruthenian
Ruthenian Bible by Francysk Skaryna, 1517, first ever book printed in Eastern Europe
The cover of the copy of the Dictionary of the Belarusian Local Tongue by Ivan Nasovič preserved at the Francis Skaryna Belarusian Library and Museum