The history of Murong Xianbei and five Yans last two hundred years from Mohuba move to Zhongyuan during the beginning of the three kingdoms period to Northern Yan annihilated by Wei system (431), the period of history is long as Wei-Jin period. In this thesis, the way Murong Xianbei transforms his role and become one of five Hus in china during Wei-Jin period is discussed. The times background is great unification collapsed and Hu tribes are becoming leader role in Chinese history stage. How Murong Xianbei change itself, how evolution about relationship between Murong Xianbei and other Hu Han tribe and how those changes influence the rise and fall of five Yans regime during this period is also discussed.The thesis states three questions. First, the whole story of vassal state experience for Murong Xianbei during wei-jin period and the establishment process of Yan kingdom. Murong Xianbei stay with other Xianbei tribe since move to Zhongyuan at the beginning of the three kingdoms period, and become the intermediate force in western Liaoning during the period of Cao Wei and Gongsun family confronted each other. Later, Murong Xianbei become the vassal Hu tribe on Wei-Jin dynasty because western Liaoning be included into Cao-Wei vassal state management system after Gongsun family annihilated by Cao-Wei just like Xiongnu and QiangDi tribe which moved to Zhongyuan in Han dynasty. Murong Xianbei has no choice but hanization during Wei-Jin period because which fall into predicament in northeast area ethnic conflict and his identity of vassal Hu tribe. Benefit from hanization reform, Murong Xianbei showing itself at the end of Jin dynasty and revealing itself in northeast area. The process of Hanization reform had some weak points, thus Murong Xianbei encounter the continuous crisis, but all kinds of difficulties overcame through the great efforts of Murong Gui and Murong Huang, and the country transform from vassal state to a independent kingdom, set up the Yan regime which dominate by Murong Xianbei finally.Second, the rise and fall of Former Yan and tribe split into groups caused by imperial clan faction. Zhongyuan area falls into violent turmoil when Shihu died in A.D349(Yonghe five years). Murong Jun takes occasion to move southward Zhongyuan and set up the Former Yan occupied Guandong but encounter unprecedented tribe situation. Therefore, Former Yan dynasty approbates various local powers and to ensure Murong Xianbei tribe in the dominant position, meanwhile, continue to implement the military reward system which allowed the military nobles have their own YinHu since Murong Huang period. These factors cause the contradiction between Military camp system and prefecture system which lead to decline of the country. After annihilated by Former Qin, Murong Wei and other imperial kinsmen not only preferential treated by Fujian but also keep the subordinate relations with other Xianbei tribes, become a political power which can influence Former Qin situation gradually. On the other hand, Murong Chui who surrender to Former Qin because of imperial clan faction establish the Hu-Han group lead by himself. The split of imperial clan make east and west two kinds power has appeared during their restore nation movement after the battle of Feishui, and two subtribes have different restore nation road, therefore, the Late Yan and the Western Yan is established finally.Third, the different characteristics of these ethnic groups between Western Yan and Late Yan and the ethnic meaning of "south and north split". The main body of Murong Xianbei that survived from the Former Yan congregated in the Western Yan, the Late Yan established depends on Hu tribes force in hinterland of Guandong such as Dingling, Wuheng, Fuyu, Duan Xianbei, Tuge. The two Yans form confrontation in Guandong area, but national power between two Yans is quite different. The Late Yan reach heyday after destroy the Western Yan and unionize the Guandong area in A.D394(Taiyuan19years). But the heyday is very short, the Yan-Wei alliance break up in Taiyuan20years and the Northern Wei regime set up by Tuoba tribe which move southward Zhongyuan. Late Yan split one into two under attack by Northern Wei. The essential of south and north split is not only in territory aspect, but also the relationship between Murong tribe and northeast Hu tribe who established the Former Yan together with Murong tribe become estranged gradually because the feature of Later Yan is multiethnic. So, Murong tribe set up the regime with Han tribe or dominant position is replaced by Huizated Han people after the territory of Late Yan split one into two which lead to the Southern Yan and the Northern Yan is discrete in north-south and regime change, and present different Huization and Hanization situation between north-south countries in characteristics of these ethnic groups. |