Question

The Line of Demarcation established a boundary between Spain and Portugal.

Answer 1

The Line of Demarcation between Spanish and Portuguese territory was first defined by Pope Alexander VI (1493) and was later revised by the Treaty of Tordesillas (1494). Spain won control of lands discovered west of the line, while Portugal gained rights to new lands to the east. 
The idea of this was to separate distinctively the colonies of Spain (most of latin america) and Portugal (Brazil and most of Africa) thus avoiding a war.

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