Complex sentence: Using technology that was advance for that time, the Dutch were able to convert enough marshland to allow large estates to form all along the Gironde as the Bordeaux wine regions of Margaux, Saint-Julien, Pauillac and Saint-Estèphe took shape.
Split into simpler sentences: Using technology that was advance for that time, the Dutch were able to convert enough marshland to allow large estates to form all along the Gironde. Soon the Bordeaux wine regions of Margaux, Saint-Julien, Pauillac and Saint-Estèphe took shape.