This unusual and intriguing study of nationhood explores the nineteenth-century confrontation of ideas that transformed the kingdom of Siam into the modern conception of a nation. Fundamental to the author's analysis is the assumption that notions of national identity are discursively constructed and therefore are subject to change. Here, modern Thailand is viewed as its territory and related values and practices, or what the author terms its "geo-body." Thongchai Winichakul's compelling narrative explores the emergence of this new territorial entity by examining the influence of modern mapping techniques on Thai conceptions of nationhood. Before the late nineteenth century the Siamese understanding of the territory of a state precluded the delineation of boundaries in the modern sense. Overlapping or multiple sovereignties were common, whereby a small state might pay tribute to two or more sovereign overlords and still remain sovereign itself. Areas where no country claimed sovereignty also existed, creating a sort of buffer corridor. As Europeans moved into the region in the nineteenth century, bringing with them the new geography and technology of mapping, the confrontation between modern and indigenous conceptions of boundary and sovereignty caused misunderstandings in the conduct of diplomatic relations, confusion in surveying and boundary demarcations, and armed military clashes. The Europeans, and later the Siamese rulers, desired a country defined by the new technology of mapping. Ultimately the mapped geo-body replaced the indigenous territory, and a nation emerged. Siam Mapped challenges much that has been written on Thai history because it demonstrates convincingly that the physical and political definition of Thailand on which other works are based is anachronistic. The work is an important contribution to the study of Thai history, to the study of Southeast Asia - and indeed much of the world - in the nineteenth and early twentieth centuries, and t