本文係據第一屆「東吳大學陶晉生院士歷史講座」第一場演講增訂而成。六世紀末到十世紀初的隋（581－619）唐（618－907）兩朝歷史，在時人記載和後人著述中，大都被強調為幅員廣袤而統一的盛世。誠然，安史之亂（755－763）前的唐朝，委實可稱興盛。當時身為農耕地區編戶齊民的皇帝，同時被草原遊牧族群尊為天可汗。其後，八世紀中葉直到晚唐五代時期，政局動盪、多族群複合體的社會分化，特别是藩鎮分據地區，在胡風浸潤下而衍生政治、軍事、文化上的多元交疊。特別值得人們注意的是，跨文化的衝突與互動既促進彼此的涵化與融合，也構成朝代更迭和異族建立邦國的誘因或機緣。因此，探究中原王朝與遊牧族群在唐宋變革時期的演變與傳承，是本文的主旨所在。

This article is a revised and expanded paper on the basis of an inaugural academic speech for the “First Forum of the Historical Lectures, dedicated to Academician Tao Jin-sheng” at Soochow University. The history of the Sui (518-619) and Tang (618-907) dynasties from the end of the sixth century to the beginning of the tenth century is usually emphasized as a powerful and unified era with vast territory in contemporary records and later works. The Tang Dynasty before the An-Shih Rebellion (755-763) was indeed prosperous. The ruler of China at that time was an emperor of farming areas and was revered by nomadic people as the Tengri Qaghan. Later, from the middle of the eighth century to the late Tang and Five Dynasties, the political turmoil and the divisions arising within multi-ethnic societies, especially in the “fanzhen” (藩鎮; regional military governors), were influenced by non-Han peoples, resulting in multiple overlaps in politics, military affairs, and culture. In particular, it is worthy to note that cross-cultural conflicts and interactions not only promote mutual assimilation and integration of each other, but also constitute an incentive or opportunity for dynastic change and for tribes to establish new states. Therefore, it is the purpose of this paper to explore the evolution and inheritance of the Central Plains dynasties and nomadic ethnic groups during the Tang-Song transformation.