Final answer:
The Treaty of Tordesillas, agreed upon in 1494, established a line of demarcation separating the Spanish and Portuguese claims in the New World.
Step-by-step explanation:
The line of demarcation separating the Spanish and Portuguese claims in the New World was established by the Treaty of Tordesillas in 1494. This agreement was drawn up in the aftermath of the 1492 Columbus landfall, which escalated the rivalry between Spain and Portugal for new lands. The treaty clarification involved a north-to-south line drawn through South America, with Spain gaining the territory west of the line and Portugal securing the lands east of the line, inclusive of the east coast of Brazil.
This boundary, described in the Treaty of Tordesillas, awarded all the land to the west of this line to Spain, while all the land to the east of this line was awarded to Portugal. The partition was drawn without reference to the sovereignty of the indigenous people who lived there. Over time, however, sustained incontestable claims from other nations nullified the treaty.
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