Guanzhong has been a battleground for military strategists since ancient times. Why did you withdraw from the historical stage after the Tang Dynasty?

Guanzhong has been a battleground for military strategists since ancient times, mainly because Guanzhong area is rich in water resources, suitable for climate and fertile land, and was the main grain producing area in the early days. Coupled with the natural barriers in the southeast and northwest, it can be attacked and retreated, and its strategic position is naturally high. The gradual decline of Guanzhong's strategic position is mainly caused by the gradual shift of economic center of gravity and military center of gravity, and these two changes are caused by many factors.

The shift of economic center of gravity

As early as the Spring and Autumn Period and the Warring States Period, Guanzhong area was rich in water resources, suitable in climate and fertile in land, and was an important grain producing area. Land of abundance? Refers to the Guanzhong area, which shows the wealth of Guanzhong at that time. Later, with the development of central Sichuan, Guanzhong was the best way to enter Sichuan. Guanzhong and central Sichuan are two major grain producing areas that are easy to defend but difficult to attack, which makes Guanzhong's strategic position rise rapidly, which is also an important reason why Guanzhong has been chosen as the capital from Qin and Han Dynasties to Sui and Tang Dynasties.

China is a land of abundance.

However, with the passage of time, the economic status of Guanzhong area is gradually declining, the main reasons are as follows:

1, serious soil erosion. Due to the long-term existence of Guanzhong area as the national capital before the Tang Dynasty, the rapid economic and social development brought about a rapid population expansion, coupled with the large-scale immigration of dynasties to Guanzhong, the impact of the sudden population increase was the increase of cultivated land area, but due to the influence of the geographical environment in Guanzhong area, there were not many areas suitable for farming, so a large number of land reclamation became inevitable. The consequence of land reclamation is that vegetation in Guanzhong area is seriously damaged and soil erosion is serious. Land of abundance? It became the later Loess Plateau. The rapid decline of grain output and the lack of good grain transportation channels have greatly restricted the economic development in Guanzhong area.

2, devastated by war. It is precisely because of its high strategic position that Guanzhong region has been devastated by war for a long time. First, Xiang Yu set fire to Xianyang at the end of Qin Dynasty, then Li Jue, Guo Si, Marten and Han Sui fought in Chang 'an at the end of Eastern Han Dynasty, and then Liu Yao sent his troops to attack Chang 'an at the end of Western Jin Dynasty. Five random China? Guanzhong, which suffered heavy losses, and then to the Tang Dynasty? An Shi rebellion? 、? Huang Chao rebellion? When Tubo and Uighur attacked Chang 'an, Guanzhong was the first to bear the brunt of the Five Dynasties and Ten Kingdoms. Long-term war led to a devastating blow to Guanzhong's economy and a sharp drop in population, and Guanzhong never recovered its former glory. ?

3. The economic center of gravity moves south. Due to the long-term influence of the war in the northern Central Plains, Soochow also experienced the development of Jiangnan. Yongjia Du Nan? 、? An Shi rebellion? Large-scale South Crossing to the Central Plains and the Late Northern Song Dynasty? Jane Yan Du Nan? With the large-scale southward migration of gentry, farmers, craftsmen and businessmen in the Central Plains, the economy of Jianghuai and Jiangnan areas has developed rapidly. Since the Southern and Northern Dynasties, South Convenience began to replace the Central Plains as the national economic and cultural center.

Environmental changes lead to problems in grain reserves, war leads to serious damage to the foundation, and the shift of economic center of gravity to the south leads to the decline of economic status. Under the comprehensive influence of these factors, the strategic position of Guanzhong area naturally declined.

Military center of gravity shift

The shift of military center of gravity is mainly caused by changes in the surrounding situation. From the Qin and Han Dynasties to the Sui and Tang Dynasties, the main threats in the Central Plains mainly came from ethnic minorities and nomads in the northwest, but the Guanzhong area was surrounded by Tongguan (Hanguguan), Sanguan (Great Earthquake Pass), Nanwuguan (Languan) and Beixiaoguan (Jinsuo Pass). Is it true?/You don't say. 4. Blocked land? Not only easy to defend but difficult to attack, but also close to the strategic frontier, the military status is naturally extremely high.

Guan zhong is? 4. Blocked land?

However, with the change of the surrounding situation, the military status of Guanzhong area is also declining:

1, the gradual pacification of Longxi area. Since the Qin and Han Dynasties, with the gradual deepening of the exchanges between the Central Plains regime and the western countries, the exchanges between Longxi and the Central Plains region have also become more frequent. In addition, the Central Plains regime has repeatedly used troops to the northwest. After the Sui and Tang Dynasties, Longxi area was basically in the hands of the Central Plains regime. After all, the Sui and Tang royal families were born in Longxi nobles. With the gradual pacification of Longxi, the western defense line in Guanzhong area lost its original function. Since then, the threat of the dynasty to the west mainly came from the western regions, and the strategic frontier extended to Gansu and Ningxia generations. Guanzhong area has changed from a strategic frontier to a second line of defense.

Jiubian Town in Ming Dynasty

2. The threat from the north is gradually deepening. Although the northwest has gradually calmed down, the threat from the north has been deepening. The rise of Xianbei, Turkic, Mongolian and Jurchen always threatened the northern part of the Central Plains regime, thus making the military position along the Great Wall begin to rise. Northern border ports such as Gansu, Ningxia, Yulin, Datong, Fu Xuan, Taiyuan, Jizhou, Youzhou and Liaodong are becoming more and more important.

It can be said that with the changes in the surrounding situation, the Guanzhong area has been relatively safe, and it is an inevitable trend for the military center of gravity to move westward and northward. Even from the strategic radius, the status of the Central Plains is higher than that of the Guanzhong area.

To sum up, the decline of strategic position in Guanzhong area is a historical necessity and the result of the comprehensive influence of many factors.