The Han Dynasty (206 BC ~ 220 AD)
At this time, the Xiongnu was still very powerful. Han Gaozu, the first emperor of the Han Dynasty tried to defeat the Xiongnu but was almost killed himself. For the next sixty years during the reign of the Han Dynasty, the emperors chose to make peace with the Xiongnu through the paying of tributes and marriages. However, this did not give an ideal result as the continual attacks never ended on the North of China. After this, Han Wudi succeeded the throne. He attacked the Xiongnu and defeated them, driving them further towards the North.
Han Wudi, being one of the wisest emperors in the history of China, realised that the Xiongnu was still a menace to his land. Therefore, in order to improve the defence system, he ordered for two constructions of the Great Wall. The two constructions were just as big as the part of the wall built by the Qin Dynasty each. This part of the wall also acted as a protection to the traders and travellers along the Silk Route. Without the Great Wall, the Silk Route could never be opened as bandits and tribes would attack the traders. Along the Silk Route, goods were transported. Silk was brought from China all the way to Rome where it was sold at the price of gold. The East and the West were connected through the Silk Route. It not only brought economical benefits to the countries, but also encouraged the exchange of culture, ideas and religion. Buddhism was first introduced to China through this route.
Towards the later part of the Western Han Period, (the Han Dynasty is split into two periods, the Western and the Eastern Han Periods) the emperors continued the tradition of paying tributes and marriages to the northern tribes to make peace with them. During the reign of the first emperor, Guang Wudi, of the Eastern Han Period, the country was relatively weak after the civil wars. The Xiongnu took the advantage and made frequent attacks in the North. Guang Wudi had no choice but to improve the defence. He further enhanced the defence system of the Great Wall.
After this, the Xiongnu was split into two tribes, the North and the South. They fought against each other and thus eased the attacks to China. Besides, the Southern tribe, which was closer to China, was gradually influenced by the Chinese culture and this helped to further peace along the northern border of China.
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