19世紀英國是海上霸權國家，擁有海外眾多殖民地的英國，號稱「日不落國」。然而，英國卻奉行孤立主義，不與歐洲強權結盟，試圖以權力平衡方式，控制整個世界。英國政策影響國際體系的運作，也決定眾多國家的發展與生存。當東南亞地區各國相繼淪為英法荷美等國的殖民地，唯有暹羅（Siam）卻能維持主權獨立，並在第一次世界大戰後，加入國際聯盟（League of Nations），形式上與英法等國家平等而坐。然而，1893年由法國引發的「湄南危機」，不僅讓暹羅受到割地賠款的恥辱，其存亡更是掌握在英法兩國一念之間。暹法英三國面對「湄南危機」的交涉，展現出強權國家勢力的消長，以及小國如何在強權決策下的國際結構下生存。

In the 19th century, Britain was a maritime hegemonic power with numerous overseas colonies, and was known as the “empire on which the sun never sets”. However, Britain pursued isolationism and refused to form alliances with European powers, attempting to control the entire world through a balance of power strategy. British policies influenced the functioning of the international system and determined the development and survival of many countries. When Southeast Asian countries fell one after another to the colonial powers of Britain, France, the Netherlands, America, and others, only Siam (Thailand) managed to maintain its sovereignty and independence. After World War I, Siam joined the League of Nations and formally sat on an equal footing with countries like Britain and France. However, the “Mekong Crisis” triggered by France in 1893 not only brought shame to Siam through land concessions and indemnities, but also placed its survival in the hands of the United Kingdom and France. The negotiations between Siam, France, and the United Kingdom during the “MaeNam Crisis” demonstrated the waxing and waning of great power influence, as well as how weaker countries can survive in the international structure of decision-making by stronger powers.