Complex sentence: Despite internal and external threats, and more religious discord than the West, these provinces remained prosperous contributors to tax revenue; despite the huge extortions of Attila's peace treaties, tax revenue generally continued to be adequate for the essential state functions of the Eastern empire.
Split into simpler sentences: Despite internal and external threats, and more religious discord than the West, these provinces remained prosperous contributors to tax revenue. Despite the huge extortions of Attila's peace treaties, tax revenue generally continued to be adequate for the essential state functions of the Eastern empire.