文章以兼跨长城南北的唐前期为例,旨在分析以汉人为主体建构的政权超越农耕区进入草原所受到的限制及其因缘,认为农耕王朝兼跨的局限乃在于自身的生计方式与草原游牧生计存在着难以兼容的张力。如何有效地将迥然有别的游牧与农耕生计为依托的群体共融在一个政权体内,虽然耗费了唐朝历代统治集团大量的精力和心血,但终究以彼此的分隔而结局。此种衍化的路径似乎暗示“纯粹”的农耕王朝尚不足以跨越南北兼跨的障碍,该任务则落在了源自中原周边尤其北方的政治势力及其含括中原模式而南北兼容的王朝(如元、清)肩上,然而这种政治体同样面临着内部诸种势力与群体间的磨合张力。 Taking the inter-spanning of the Great Tang and the North and the South as early pre-Tang period as an example, the article aims to analyze the restriction and its cause of the regimes that take Chinese as the main body to construct beyond the agricultural areas and enter the grasslands. The limitation of the farming dynasties and the cross lies in their livelihood and grassland Nomadic livelihoods have incompatible tensions. How to effectively bring together vastly different groups based on nomadic and agricultural livelihoods into a single political power has eventually ended in isolation from each other despite consuming much of the energy and effort of the ruling groups of the Tang Dynasty. This evolutionary path seems to suggest that “pure” agrarian dynasties are not enough to cross the inter-Korean obstacle. The task falls on the political forces originating from the periphery of the Central Plains, especially the north, and its compatibility with the Central Plains Dynasty (such as Yuan, Qing) shoulder, however, this kind of political body also faces the tension between various internal forces and groups.