Complex sentence: During the conquest of Kiev on August 31,1919 by the Denikin Army who persecuted the Ukrainian intelligentsia, Leontovych returned to Tulchyn with his family.
Split into simpler sentences: During the conquest of Kiev on August 31,1919, the Denikin Army persecuted the Ukrainian intelligentsia. Because of this, Leontovych returned to Tulchyn with his family.