City Defense Of He-xi Prefecture And County Cities In The Early Tang

In the early Tang, under the special social environment of northwest region,He-xi Prefecture and county cities reflected many features such as the important town of the Silk Road, multi-ethnic coexistence and the border district administrative center. In order to ensure normal exchange between the East and the West, frequent contact among ethnicities, and effective administration in He-xi area, it was extremely essential to establish city defense. Therefore, the Tang government built the city defense system that was mainly military defense and based on social balance. Mainly included the screen protective system of Army, Shouzhuo, City, Town, Shu, etc., which had some focal point and very wide and located out of the cities; Three layers external protective system that was composed of a deep ditch to round every city, sheep and horses cities, city wall; Multiple structure system such Luo city(outer city), Zi city(inner city), fang(residential area), Shi(markets), and so on; Garrison inside cities and out of locality system; Feng, Yi and other information systems; General's office person of ability system; Warehouse reserve and social balance system. Because of the important geographical position strategic and the special social security problem, the He-xi Prefecture and county city defense had formed Trinity characteristic with the national defense and the security defense. The city defense soldiers had a hand in Tuntian to bring about He-xi area's agricultural advance; A large number of people of city defense formed the consumer market, had promoted the prosperity of the commerce; The city defense ensured traffic and military assistance, made He-xi Prefecture and county cities become the rear base to administer Central Asia. However, the city defense had its limitation, such as impotent military might at times (it offered an opportunity of Tibetan expanded in north-west area), because of the condition between the country and the locality. It, to a certain extent, had influenced on the valid function of city defense.