Complex sentence: Her mother belonged to the Nemanjić dynasty while her father founded the Lazarević dynasty and was the Serbian ruler who created the largest and most powerful state on the territory of the disintegrated Serbian Empire known in historiography as Moravian Serbia.
Split into simpler sentences: Her mother belonged to the Nemanjić dynasty while her father founded the Lazarević dynasty. He created the largest and most powerful state on the territory of the disintegrated Serbian Empire, a state known in historiography as Moravian Serbia.