structural:summarization
European colonization

In 1494, Portugal and Spain, the two great maritime European powers of that time, on the expectation of new lands being discovered in the west, signed the Treaty of Tordesillas, by which they agreed, with the support of the Pope, that all the land outside Europe should be an exclusive duopoly between the two countries.

The treaty established an imaginary line along a north–south meridian 370 leagues west of the Cape Verde Islands, roughly 46° 37' W. In terms of the treaty, all land to the west of the line (known to comprise most of the South American soil) would belong to Spain, and all land to the east, to Portugal. As accurate measurements of longitude were impossible at that time, the line was not strictly enforced, resulting in a Portuguese expansion of Brazil across the meridian.

Beginning in the 1530s, the people and natural resources of South America were repeatedly exploited by foreign conquistadors, first from Spain and later from Portugal. These competing colonial nations claimed the land and resources as their own and divided it into colonies.

European infectious diseases (smallpox, influenza, measles, and typhus) – to which the native populations had no immune resistance – caused large-scale depopulation of the native population under Spanish control. Systems of forced labor, such as the haciendas and mining industry's mit'a also contributed to the depopulation. After this, enslaved Africans, who had developed immunities to these diseases, were quickly brought in to replace them.

The Spaniards were committed to converting their native subjects to Christianity and were quick to purge any native cultural practices that hindered this end; however, many initial attempts at this were only partially successful, as native groups simply blended Catholicism with their established beliefs and practices. Furthermore, the Spaniards brought their language to the degree they did with their religion, although the Roman Catholic Church 's evangelization in Quechua, Aymara, and Guaraní actually contributed to the continuous use of these native languages albeit only in the oral form.

Eventually, the natives and the Spaniards interbred, forming a mestizo class. At the beginning, many mestizos of the Andean region were offspring of Amerindian mothers and Spanish fathers. After independence, most mestizos had native fathers and European or mestizo mothers.

Many native artworks were considered pagan idols and destroyed by Spanish explorers; this included many gold and silver sculptures and other artifacts found in South America, which were melted down before their transport to Spain or Portugal. Spaniards and Portuguese brought the western European architectural style to the continent, and helped to improve infrastructures like bridges, roads, and the sewer system of the cities they discovered or conquered. They also significantly increased economic and trade relations, not just between the old and new world but between the different South American regions and peoples. Finally, with the expansion of the Portuguese and Spanish languages, many cultures that were previously separated became united through that of Latin American.

Guyana was initially colonized by the Dutch before coming under British control, though there was a brief period during the Napoleonic Wars when it was occupied by the French. The region was initially partitioned between the Dutch, French and British before fully coming under the control of Britain.

Suriname was first explored by the Spanish in the 16th century and then settled by the English in the mid-17th century. It became a Dutch colony in 1667.