This map, of Portuguese origin, shows the Portuguese understanding of the world at the beginning of the 16th century.
It is known as the Cantino Planisphere because there is evidence that the map was brought by Alberto Cantino from Portugal to the Duke of Ferrara in 1502. There are no conclusive details about who created the map or the year in which it was completed, although everything points to it having been done in 1502 and the author being Pedro Reinel, given the similarity between the style of this map and Pedro Reinel's work.
Among other things, this map is important because it is the first to represent the line of Treaty of Tordesillas, by means of a blue line running from north to south dividing the territory that would be explored by the Spanish and the Portuguese.
It is currently preserved in the Estense Library in Modena, Italy.
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