近代中國由帝制國家向民族國家轉型，在滇西邊境土司地區的深刻表現為，由土司屬地定義國境範圍變為國界決定土司屬地範圍，境內土著由邊夷變為國民。轉變始於英殖民勢力突然而強勢的「衝擊」，無論是國家還是土著對此都未有足夠的準備，由此出現中英滇緬邊案會審制度。會案制度是在滇、緬分界後，中、英兩國指定職官，每年蒞臨邊界組成案庭會審邊民過界案件、協商邊務的制度。會案制度從1901年持續到1942年日本佔領緬甸前（有間斷），強化了國界、國家與主權的觀念，也界定了邊民的「國籍」身份。土著在一次次會案的參與、觀摩與言傳中，培養了國界與國家意識。在國家轉型進程中，土著政權成為國家構建中遭歧視與排斥的對象，難以起到本境與新的國家形態整合的作用，然而，卻在中英競爭的夾縫中得以延續。在此多方博葬中，邊民利用兩境政治差異，甚至「改變」國界，謀取生存空間或生計利益。

During the transformation of China from empire to nation- state, the borders of native chieftancies (tusi) in western Yunnan which had previously been understood in terms of chieftains' domains came to be seen in terms of national borders. Their peoples were converted from barbarous tribes to national citizens. This process began with the expansion of British colonial power in neighbouring Burma, for which neither the state nor the indigenous people were prepared. Out of the encounter emerged the practice of periodic meetings of the YunnanBurma border commission. Officials from both sides met annually to address frontier issues and adjudicate trans-border disputes. These meetings, which lasted from 1901 to 1942 when Burma was occupied by the Japanese, strengthened the notions of borders, sovereignty and nationality. Through their participation in these meetings, indigenous peoples also became aware of these concepts. In this period of nationalist transformation, indigenous sovereignty was neglected and dismissed by state- makers, making it difficult for indigenous officials to participate in the integration of their community into the nation. Nonetheless the competition between China and Burma created some space for them to maneuver. In this complex contest, border peoples made use of the political differences between the two sides to shape the development of the frontier, finding opportunities to survive and pursue their interests.