The ancient national defense of China has a history of about 4,000 years, from the establishment of Xia Dynasty in 2nd1century BC to the outbreak of Opium War in 840/AD.
The Great Wall is the continuation and development of urban construction, which was built in the Spring and Autumn Period and the Warring States Period. After Qin destroyed the unification of the six countries, the Great Wall in the north of Qin, Zhao and Yan was restored in 2 14 BC to prevent the northern Xiongnu from invading the south.
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Ancient people's attitudes and views on national defense. Ancient countries were all slaves or feudal countries, and wars between countries often manifested as power struggles between different slave owners or different feudal rulers.
The ruling class's national defense concept starts from safeguarding its own interests, attaches importance to the construction of national defense projects such as border crossings, forts and castles, and attaches importance to the recruitment and training of troops.
The army is mainly concentrated in the border areas, mainly used to defend the soil and the border or to attack the city and plunder the land. On the other hand, the people passively obey the national defense needs of the ruling class and bear arduous corvee and heavy economic burden. Therefore, the people hold a negative or contradictory attitude towards national defense.