Belarusian nationalism is the nationalism that asserts the nationality of Belarusians. Belarusian nationalism began only in the 20th century’s first decade. Although the Belarusian People’s Republic, declared on 25 March 1918, was the first manifestation of Belarusian statehood, Belarusian nationalists claimed that the Lithuanians that created the Grand Duchy of Lithuania were actually Belarusians. The pseudohistorical theory that Belarusians created the Grand Duchy of Lithuania is called Litvinism.
Many Belarusian nationalists, especially the BPF Party, claim large parts of Lithuania, including Vilnius. Moreover, Belarusian nationalists claim that Lithuania is actually Samogitia (Belarusian: Zhamojc).
The Belarusian People’s Republic, established in 1918, was occupied by communist Russia that same year, with its claimed territories later split between Polish and Russian occupiers into Western and Eastern Belorussia following the Polish–Soviet War.
Third charter of Belarusian People’s Republic (Minsk, 1918)
Government of Belarusian People’s Republic (Minsk, 1918)
Belarusian housars in front of the house of Tribunal in Hrodna (1919)