Why do the majority of Brazilians speak portuguese and majority of Colombians speak spanish?

During the colonization era, different countries started colonizing different areas. It was the age of exploration and the new lands in America were being discovered. Spain and Portugal got into an argument relating to their land as both had explorer search south America. Their solution was an invisible vertical line along the center of the earth.

They then assigned the west part of the line to Spain and the east was given to the Portuguese. Now brazil is found on the eastern side and hence most people speak Portuguese here. While, Colombia is located at the west part of the line and so has mostly Spanish people speaking Spanish.

When the Europeans were exploring new lands in the Americas during the Age of Exploration, different countries that spoke different languages were colonizing different parts of South America. Both Spain and Portugal had explorers exploring South America, but they were in conflict with each other regarding the areas that they were exploring. They decided to come to an agreement. They drew an invisible vertical line down the center of the earth.

Spain could only colonize and explore areas west of the line whereas Portugal could only explore areas east of the line. Since Brazil is located in the far east of South America, it was mostly colonized by the Portuguese which is why people in Brazil speak Portuguese. Colombia is located further west so they were colonized by Spain and the people there speak Spanish.