Araucanization of Patagonia

The Araucanization of Patagonia (Spanish: Araucanización de la Patagonia) was the process of the expansion of Mapuche culture, influence, and its Mapudungun language from Araucanía across the Andes into the plains of Patagonia. Historians disagree over the time period during which the expansion took place, but estimate it occurred roughly between 1550 and 1850.

Amerindian peoples of the pampas, such as the Puelche and Tehuelche, adopted the Mapudungun language as their main language (both of their names are in Mapudungun). Together with Quechua, Aymara, Guarani, and Nahuatl, Mapudungun was among the few Amerindian languages that expanded in use on the continent after the beginning of European colonization. This area of the Patagonia was generally isolated from European settlement until late in the 19th century.

The Mapuche who migrated to Patagonia lived often as nomads. As European settlers established frontier settlements, the Mapuche raided them for cattle or looted their produce. They drove off the cattle stolen in the incursions (malones) and took them to Chile through the mountain passes to trade for goods, especially alcoholic beverages. The main trail for this trade was called Camino de los chilenos and ran a length of about 1,000 kilometres (600 mi) from Buenos Aires Province to the mountain passes of Neuquén Province.

The lonco Calfucurá crossed the Andes from Chile to the Pampas around 1830 to aid the indigenous people, after Juan Manuel de Rosas, the governor of Buenos Aires, started to fight the Boreanos tribe. However, other sources directly contradict this statement, saying that de Rosas contacted the leader in Chile for help fighting against the Boreanos tribe. In 1859 Calfucurá attacked Bahía Blanca in Argentina with 3,000 warriors. Many other bands of Mapuche also became involved the internal conflicts of Argentina until the Conquest of the Desert. To counter the cattle raids (and the native peoples on horseback), in the 1870s Argentina constructed a deep trench, called Zanja de Alsina, to prevent cattle from being driven west and establish a boundary to the raiding tribes in the pampas.

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