How did Spain and Portugal divide lands between themselves in the Americas?

Spain and Portugal divided the lands they claimed in the Americas through the Treaty of Tordesillas, signed on June 7, 1494. Here's how the division was made:

1. Demarcation Line: The treaty established an imaginary line of demarcation that ran from pole to pole, approximately 370 leagues west of the Cape Verde Islands. This line divided the Atlantic Ocean and the eastern hemisphere into two halves.

2. Spanish Claims: All lands discovered or to be discovered west of the demarcation line were claimed by Spain, including the Americas, except for Brazil.

3. Portuguese Claims: All lands discovered or to be discovered east of the demarcation line were claimed by Portugal, including Africa, Asia, and parts of South America, most notably Brazil.

4. Exclusion Zones: Both Spain and Portugal agreed not to sail across or explore the other party's claimed territories without permission. This clause was included to prevent conflict and ensure that each nation could exclusively exploit its respective territories.

5. Adjustment: The treaty also included provisions for adjusting the demarcation line if new lands were discovered beyond the initial line of demarcation. However, disputes and conflicts still arose between Spain and Portugal over territorial claims, leading to further agreements and adjustments to the treaty.

The Treaty of Tordesillas played a significant role in shaping the early colonial expansion and territorial divisions in the Americas, influencing the course of European colonization and the development of the region.