Complex sentence: These territories, known collectively as the "Provincial States", retained much of their traditional powers and autonomy over their own internal affairs and were dominated by the wealthy and prominent Duchy of Brabant and County of Flanders.
Split into simpler sentences: These territories, known collectively as the "provincial states", retained much of their traditional power over their own internal affairs. The states were dominated by the wealthy and prominent Duchy of Brabant and County of Flanders.