How did the demarcation affect settlement of south America?

The demarcation, particularly the Treaty of Tordesillas in 1494, divided South America between Spain and Portugal, significantly influencing settlement patterns. Spain focused on establishing colonies in the western regions, leading to the development of major cities like Lima and Buenos Aires. In contrast, Portugal concentrated on Brazil's eastern coastline, fostering sugar plantations and later expanding inland. This division shaped linguistic, cultural, and economic landscapes, with Spanish and Portuguese remaining the dominant languages in their respective territories.