汉匈关系演变下朔方防务的形势和发展

The defense of Shuofang County under the evolution of Han-hun relationship

汉匈关系的发展和演变是公元前三世纪末到公元一世纪末中国北部边疆地区历史演进的主要线索。在汉匈政权300年的并立期间，双方的战与和循环反复出现直至南匈奴和北匈奴分道扬镳。在此期间，朔方地区在匈奴和汉政权之间多次易手，西汉朔方防务系统也经历了从无到有、再到废置的发展过程。西汉初期，朔方地区是匈奴的控制区。汉武帝北伐匈奴后，拓地千里，朔方郡的设立是其防御工程向北推进的第一步。在此基础上，朔方郡的建置不断完善，形成了层层递进的防御工程体系。呼韩邪单于附汉以后，西汉罢外城，省亭隧，朔方防务系统进入了“备而不用”的状态。两汉交替及东汉初年，匈汉在朔方地区展开激烈争夺，致使东汉不得不省并朔方郡。

The development and evolution of the relationship between the Han and the Hun regime is the main clue to the historical evolution of northern border regions of China from the end of the third century BC to the end of the first century AD.During the 300 year coexistence of the Han and Hun regime, the cycles of war and peace recurred until the Southern and Northern Hun goun our separate ways .During this period, the Shuofang region changed hands multiple times between the Hun and Han regimes, and the defense system of the Shuofang region in the Western Han Dynasty also experienced a development process from scratch to abolition.In the early Western Han Dynasty, the Shuofang area was under the control of the Hun. After Emperor Wu of Han conquered the Hun, he expanded his territory for thousands of miles, and the establishment of Shuofang County was the first step in advancing his defense project northward.On this basis, the construction of Shuofang County has been continuously improved, forming a progressive defense engineering system layer by layer.After Huhanye Chanyu annexed the Han regiem, the Western Han dismissed the outer cities,Abandoned beacon towers,and the Shuofang defense system entered a state of “preparation but not use”. During the alternation of the Two Han Dynasties and the early years of the Eastern Han, the Hun and Han regiems engaged in fierce competition in the Shuofang area, resulting in the Eastern Han having to merge Shuofang County.