The confessional situation in Siberia before and during the social cataclysm of 1917 was influenced by: mass resettlement movement, multinational population structure, religious absenteeism of the old residents. The analysis of the decisions of the congresses of believers and clergy of the Siberian dioceses in 1917 shows pluralism of opinions on participation of the ROC in political life, relationship between the church and the state, and governmental patronage of the clergy. In general, the degree of activity of Siberians in the studied area was minimal.