The monograph traces the little-known side of the life of the leadership, clergy (white and black) and parishioners of the Trans-Baikal diocese during the white statehood regime of ataman G. M. Semenov (September 1918 - October 1920); makes it possible to find out ways to adapt it to the new state legal situation, to restore its positions temporarily lost under Soviet rule. The publication is intended for teachers of educational institutions of any level, students of historical and humanitarian faculties, local historians.