- The Treaty of Tordesillas 1494 The Treaty of Tordesillas was agreed upon by the Spanish and the Portuguese to clear up confusion on newly claimed land in the New World. The early 1400s brought about great advances in European exploration. In order make trade more efficient, Portugal attempted to find a direct water route to the India and China. By using a direct water route, Arab merchants, who ...campus.northpark.edu/history/WebChron/Americas/Tordesillas.html