Complex sentence: All these led to a dramatic decrease in Ceaușescu's popularity and culminated in his overthrow and eventual execution in the violent Romanian Revolution; but by that time Romania's foreign debt was almost completely paid off.
Split into simpler sentences: All these led to a dramatic decrease in Ceaușescu's popularity and culminated in his overthrow and eventual execution in the violent Romanian Revolution. By that time Romania's foreign debt was almost completely paid off.