How did the Treaty of Tordesillas try to divide Portuguese and Spanish claims in the Americas?

The Treaty of Tordesillas was an agreement signed in 1494 to resolve territorial disputes between Spain and Portugal regarding newly explored lands.1

Initially, Pope Alexander VI established a line of demarcation 100 leagues west of the Cape Verde Islands, granting Spain rights to lands west of the line and Portugal rights to the east. Dissatisfied with this arrangement, Portugal negotiated to move the boundary further west. The final treaty established a line 370 leagues west of the Cape Verde Islands (approximately 46°30′ W).12

This adjustment was significant for Brazil, as it placed the eastern portion of the territory within the Portuguese sphere of influence, allowing Portugal to claim the region following its discovery by Pedro Álvares Cabral in 1500. While the treaty attempted to divide the New World into exclusive spheres of influence, it was never recognized by other European powers.1