This thesis presents an overview over the history of the concepts of nation and nationalism in Thailand. Based on the ethno-symbolist approach to the study of nationalism, this thesis proposes to see the Thai nation as a result of a long process, reflecting the three-phases-model (ethnie, pre-modern and modern nation) for the potential development of a nation as outlined by Anthony Smith. The four main points put forward by this thesis are as follows: First, the Thai nation is the result of a long process with roots within several cultural cores. When the modern nation came into being in the early Bangkok period, it was characterised by an indigenous interpretation different from the western understanding of a nation. Second, Thai nationalism as an ideology originated in the mid-nineteenth century. It was a consequence of an intra-elite struggle between the nobility and the monarchy. The kings actively used nationalism to strengthen their position and to bind the loyalty of the people to their institution. As a result, Thai nationalism at the very beginning was 'monarchical' with the monarch himself embedding the nation and lacking a popular component. Third, Thai nationalism in the twentieth century was characterised by alternate interpretations of the nations by different ruling elite groups. This resulted in three competing nationalisms, namely monarchical, statist, and royal nationalism. Fourth, the period since 1980 saw a revival of monarchical nationalism. The current ruler, King Bhumibol, adapted monarchical nationalism to a modern and democratic political system. He interprets the modern nation as a self-sufficient, trans-ethnic and moral community and disseminates the ideals with the help of the state via monuments, art, stamps, ceremonies, legends and festivals.