My dissertation project analyzes the crafting of notions on territory, ethnicity, and nation in the Amazonian region now shared by Ecuador and Peru, and historically known as Maynas. My working hypotheses are: (1) that between the late seventeenth and early nineteenth centuries, Jesuit and Franciscan cartography played an important role in the systematization, and eventual nationalization, of the knowledge about territories and societies in Western Amazonia, and (2) that this process of knowledge making on Maynas depended upon relationships missionaries established with indigenous Amazonian societies. My project thus aims to study how ideas on territoriality and ethnicity came to be formulated as the result of a process in which both missionaries and Amazonian Indians participated, and how Maynas and its inhabitants came to be considered either Ecuadorian or Peruvian after independence. My general goal is to generate new theoretical and practical appreciations in regard to the crafting of spatial and national identities.