Why have many South American Indigenous languages become extinct?

Many South American Indigenous languages have become extinct due to a combination of historical and social factors following European conquest and colonization. The primary reasons for this decline include:12

• Population Loss: The arrival of Europeans in the 16th century led to the near extinction of many Indigenous groups through a combination of violence and the introduction of foreign diseases. When the speakers of a language disappear, the language itself often ceases to exist.32
• Acculturation and Assimilation: Many Indigenous peoples were absorbed into colonial society, leading them to adopt European languages such as Spanish or Portuguese for public transactions and daily life.23
• Linguistic Displacement: Certain Indigenous languages, such as Quechuan, were actively spread by colonial authorities for government and missionary purposes, which often resulted in the displacement or reduction of smaller, local Indigenous tongues. Similarly, the development of língua-geral (a hybrid of Tupí-Guaraní and Portuguese) served as a medium of communication that eventually replaced many original languages in Brazil.124
• Bilingualism: In many communities, populations became bilingual, with an Indigenous language spoken at home while a European language was used for broader communication, often leading to the eventual loss of the native idiom among younger generations.12