This political faction was organized in 1903 when it split from the Bolsheviks
[DOC] [TLE] Bolshevik - New World Encyclopedia [PAR] Jun 15, 2016 ... 1.1 The 1903 split; 1.2 Origins of the name; 1.3 Beginning of the 1905 Revolution 
... 2 Political philosophy; 3 Derogatory Usage of "Bolshevik" ...