The disadvantages and essence of the Tang Dynasty's association with Huihe Kingdom during the years of 745-840

After TuJue,Xueyantuo,the Huihe nationality which occupied the northern desert made full use of characteristics of themselves to open up atmosphere.After the middle of 8th century,the Tang Dynasty's many actions reinforced this possibility,thus also reflected the Tang Dynasty's fact of prosperity to decline.The Huihe kingdom of northern desert was on an initiative footing in the friendly association with Tang and once controlled the internal affairs and diplomacy of Tang Dynasty many social problems and negative influence produced form this association.The article will explore the root cause of these problems' existing and difficultly solving them from following aspects Huihe helped Tang put down a rebellion;paying tribute and granging;market trade;uniting by marriage and Moni Religion being current in China.