Original sentence: However, this hadn't protected them from ethnic conflicts, especially in times of Great Depression of 1929.This would allow Soviets to carry out harsh reprisals against those Poles - begun with confiscation immense property (land, forests), persecution of religion (bishop Cieplak 1923) and eventually full scale deportation of Poles to Kazakhstan 1931-1934
Edited sentence: However, this hadn't protected them from ethnic conflicts, especially in times of economic depression of 1929.With signing the treaty, Poland practically sanctioned harsh reprisals against those Poles - begun with confiscation immense property (land, forests), persecution of religion (bishop Cieplak 1923) and eventually full scale deportation of Poles to Kazakhstan 1931-1934