Treaty of Tordesillas
The Tordesillas Meridian divided South America into two parts, leaving a large chunk of land to be exploited by the Spaniards. The Treaty of Tordesillas has been called the earliest document in Brazilian history, since it determined that part of South America would be settled by Portugal instead of Spain. The Treaty of Tordesillas was an item of dispute for more than two and a half centuries but clearly established the Portuguese in America. It was replaced by the Treaty of Madrid, in 1750 and both reflect the present extent of Brazil's coastline.