Complex sentence: Five out of fifteen committee members quit their positions after the FORA IX refused to join the RILU at its January 1921 conference, and the FORA V was split between a pro- and an anti-Bolshevik wing before the latter faction was expelled from the union in 1921.
Split into simpler sentences: Five out of fifteen committee members quit their positions after the FORA IX refused to join the RILU at its January 1921 conference. The FORA V was split between a pro- and an anti-Bolshevik wing, until the latter was expelled from the union in 1921.