本文先檢討西洋民族主義興起的政經、社會與思潮背景，也討論Nationalism的字義與界定。接著敘述民族主義從歐洲散播至拉美、亞、非、大洋洲的情況，以及今日第三世界把反殖民主義與本土形成的民族主義掛鉤。在思想與文化背景之下十八與十九世紀的法╱德文化、哲學、藝術、宗教與國民主權思想之抬頭有於國勢的增強，也促使自由的與擴張的民族主義之確立。民族主義的中心議題離不開領土、民族、社群、自決與認同諸大問題，而種族與民族的分辨，也使吾人對種族與族群有進一步的認識。至於民族主義的理論，牽連到意識形態與社經發展、理論與感情的孰重孰輕、政治與文化的交融和此一理念體系的建構與詮釋。在結論中作結綜合近幾十年來西方（特別是英、美）的著作，說明民族主義的現象，並未因冷戰的結束，「蘇東波變天」，東西文明衝突，或恐怖主義，以及反恐戰爭而告消失。在很大的程度內，民族主義在二十一世紀的世局與思潮中仍會扮演其一定的角色。

　　　　　This treatise deals firstly with the etymology of "nation" and "nationalism", the common definition and usage of nationalism. It then traces the rise of nationalism in the emergence of national states in the mid 17th -century Europa. The widespread export of nationalism to Latin America, Africa, Asia, and Oceania had a strong connection with colonialism and imperialism of European powers since the 19th century, which further generated two world wars in the following century. Even the newly emerging nations have resorted to the hegemonial strategy of the Western powers. Thus the indigeneous, local elites have established their own sovereignty by declaring national independence of colonial metropolitan powers. Thus, nationalism became the impetus to and driving force of nation building of the third world countries. Instead of the traditional nation-states, they have now tried hard to consolidate state-nations. Subsequently, the essay discusses the five main factors or main topics of nationalism, namely, national territory, nations and ethnicities, societal community, self-determination and autonomy, as well as national identity. Finally, the paper exposes briefly the recent literature on the theories of nationalism basically in the English-speaking world. It highlights nationalism and its aspects, including conceptualizations of ideology, socio-economic development, rational choice and effectual and emotional elements, politics or culture, socially imagined and constructed mass psychology and ethnic symbolism. In conclusion, the author regards that the phenomena and problematics of nationalism play a big role in the beginning of the 21st century. Nationalism surely will not wither-away or totally disappear after the end of the Cold War, or even the "End of History".