Did the Great Wall of China Work?
Great Wall of China worked effectively as a military defense project in history.
As early as 7th century BC, the state of Chu began to build the Great Wall in order to resist the threat of the northern nomadic people. Although the Great Wall was generally 3 - 4 meters (3.3 - 4.4 yards) high at that time, it effectively delayed the assault of the nomads. After Emperor Qin Shihuang unified China, he joined together the separate sections built by previous states to form a huge complicated frontier defence, resisting the invasion of the northern Huns and consolidating his rule. The Great Wall was extended during Han Dynasty (202 BC - 220 AD), also aiming to protect the people inside from the invasion from northern Huns. And it was also built to protect the land from invasion during most of later dynasties. Besides, the Great Wall also protected the Silk Road, an international trading route extending from Xi’an to European countries.
Historically, Qin (221 - 207 BC), Han and Ming (1368 - 1644 AD) were the three dynasties most frequently invaded by the northern nomads and were also the three most active dynasties in the construction of the Great Wall, which indirectly proved the effective military defense function of the Great Wall of China.
The Great Wall of China is a multi-functional military defensive system and it worked effectively like this:
Delivering message: The soldiers stationed at the beacon towers transmitted messages by fire or smoke to warn their troops once the enemy was found approaching.
Defending: The Great Wall is generally located in high terrain, like a military screen to defend the people inside.
Transporting troops and supplies: The wide passages on the top of the wall are beneficial to troop’s movement and supplies’ deliver during the battles.
Aggressing and Territory Expansion: Chinese troops relied on the Great Wall to attack the Huns. If they won, they kept advancing and took over the territory of the nomads; if they lost, they returned and sought defense from the Great Wall.
It did not success every time and was broken through not only once.
In the face of attack, the Great Wall helped organize defense and reduce the losses caused by nomadic people from the north. In the era of cold weapons, it certainly worked well. In the over 2,000 years’ history from the Qin Dynasty to the Qing Dynasty (1644 - 1911 AD), there was only one person - Genghis Khan who broke through it.
See more Genghis Khan breached China Great Wall
In the middle and late Ming Dynasty, gunpowder was gradually applied to the military. The defensive effency of the Great Wall gradually weakened. When it entered gunpowder era after the 19th century, the function of Great Wall as a military defense project completely ended. At present, the Great Wall is a popular tourist attraction and a cultural symbol of the Chinese nation.