Complex sentence: Due to its long-distance trade, Nordhausen was prosperous and influential with a population of 8,000 around 1500, that was the third-largest in Thuringia after Erfurt, today's capital, and Mühlhausen, the other free imperial city in the Land.
Split into simpler sentences: Due to its long-distance trade, Nordhausen was prosperous and influential, with a population of 8,000 around 1500. It was the third-largest city in Thuringia after Erfurt, today's capital, and Mühlhausen, the other free imperial city in the land.