All of these empires developed during the Renaissance period with the introduction of trade and the use of the Silk Road. The Babylonian and Charlemagne empires had a greater competitive advantage in the use of trade which helped the Babylonians and Romans learn from different cultures along the trade route. The heavy taxes imposed on people made it difficult to trade or acquire wealth. Famine due to the flooding of the Nile River damaged trade as did the plague that traveled along the trade routes. During the Scientific Revolution the Charlemagne and Mongol empires gain a competitive advantage in learning. Charlemagne knew the importance of education and education of his people and made it one of the many achievements during his rule. The Mongols developed a strong interest in science and astronomy by developing a mathematical system still used today and learning how the universal system provides models for how the earth reacts to weather patterns, as well as the dangerous results of those models. The ancient civilization of empires explains much of the history left in records that have helped astrologers and scientists explain how life that existed long ago evolved