Where Is Sanwei And Heishui?:"Sanwei Is Tibet" And The Scholars’ Recognition Of Chinese Borderlands Since Qing Dynasty

"Sanwei" and "Heishui" is a set of geographic concepts in "Yugong", these concepts represent western border of Yongzhou and Liangzhou. Because of the ambiguity of description of position of "Sanwei" and "Heishui" in "Yugong", many scholars want to clarify this issue. From the perspective on historical geography, with the evolution of Han peoples’ understanding of frontier, there were many hypothesis of this issue:"Dunhuang","Xiqiang","Yunan" and "Qinghai"."Sanwei is Tibet" was a new concept emerged after the Emperor Kangxi of Qing dynasty.From the Qing Dynasty to contemporary, the concept "Sanwei is Tibet" experienced two different stages of development.:Before the Daoguang period, the debate around the issue was mainly a problem of history and geography. Many scholars of Qing used textual and geographic discovery to criticize the former hypothesis about "Sanwei", at the meantime,"Sanwei is Tibet" had prompted them to rethink "Yugong" territory and the distribution of ancient people. The second stage is from late Qing Dynasty to the present, as the crisis of Chinese frontier emerged,"Sanwei is Tibet" became a historical proof of Chinese sovereignty in Tibet since Yugong period., it also played an important role in the formation of "Sino-Tibetan homology theory" and "Qiang and Tibetan homology theory". Along with the change of "Sanwei", the Han peoples’ imagination of Tibetan was also changing, it has also affected today’s research.This article want to discuss the development and evolution of "Sanwei is Tibet" in Qing dynasty, ROC and PRC so as to solve three question:1. Based on the theory "Sanwei is Tibet", how did the scholars of Qing revise and overthrow the former views of "Sanwei" and "Heishui";2.How did the theory "Sanwei is Tibet" reconstruct the area of "Jiuzhou", and impacted on peoples’ frontier concept in reality.?;3.How did the modern nationalism thought use and reform the theory "Sanwei is Tibet" to prove the "Sino-Tibetan homology theory", and make it to conform to the need of nationalism construction. I hope this discussion can help to recognize the authenticity of the ancient legend, while will also benefit the research of modern nationalism construction.