What was one of the main reasons for the establishment of the Great Wall of China?

The main reason for the establishment of the Great Wall of China was to protect against northern invasions. Throughout Chinese history, particularly during the various dynasties, the northern tribes, such as the Mongols, posed a significant threat to Chinese settlements and agricultural lands. The construction of the Great Wall was aimed at fortifying the borders of the empire, establishing defensive structures to deter invasions, and allowing for better control of trade and migration across the northern frontier.

While marking territory was a part of its function and the wall could have facilitated trade by defining boundaries, those were not its primary purpose. It certainly was not built to serve as a tourist attraction, which is a consideration made much later, as the Great Wall is now recognized as a significant historical and cultural monument. The wall’s construction reflected the strategic military needs of the time and played a crucial role in the defense mechanisms of ancient China.