This innovative book rethinks the eighteenth- and early nineteenth-century history of coastal and riverine southwest Indochina, the water frontier of the title. It repositions old state-centered histories to reveal the region as a single, multiethnic economic zone knit together by the itineraries of junk traders and by the activities of many southern Chinese, settlers, sojourners, and merchants, whose local significance it explores. In so doing, it pioneers a new, nationally-neutral way of perceiving this dynamic region.