Abstract / Description: "This paper proposes a new historical interpretation of pre-modern relations between Burma and Siam by analyzing these relations within the historical context of the formation of Burmese states: the first Toungoo, the restored Toungoo and the early Konbaung empires, respectively. The main argument is that the conflictive conditions leading to the military confrontation between Burma and Siam from the 16th to 19th centuries were dynamic. The changing nature of Burmese states? conflict with Siam was contingent firstly on the internal condition of Burmese courts? power over lower Burma and secondly on the external condition of international maritime trade. The paper discusses this in seven parts: 1. Introduction; 2. Previous studies: some limitations; 3. Post-Pagan to pre-Toungoo period; 4. The first Toungoo empire: the outbreak of Burmese-Siamese warfare; 5. The restored Toungoo empire: Mandala without Ayutthaya; 6. The early Konbaung empire: regaining control of Ayutthaya; and 7. The early Konbaung empire: Southward expansion to the Malay Peninsula."...Keywords: Burma; Siam; warfare; state formation; Toungoo; Konbaung