The Mapuche are the indigenous inhabitants of Central and Southern Chile and Southern Argentina. They were known as Araucanians by the Spaniards. This is now considered pejorative by the people and the term Mapuche is the one most often used by people in conversation. Mapuche make up about 4% of the Chilean population, who are particularly concentrated in the Araucania Region.
Contrary to popular belief, the Quechua word awqa "rebel, enemy", is probably not the root of araucano: the latter is more likely derived from the placename rag ko "clayey water".
The Mapuche had an economy based on agriculture; their social organisation consisted of extended families, under the direction of a "lonko" or chief, although in times of war they would unite in larger groupings and elect a toqui to lead them.
The Mapuche are a wide-ranging ethnicity composed of various groups which shared a common social, religious and economic structure, as well as a common linguistic heritage. Their influence extended between the Aconcagua River and Chiloé Island and later eastward to the Argentine pampa. The Mapuche (note that Mapuche can refer to the whole group of Picunches (people of the north), Huilliches and Moluche or Nguluche from Araucanía or exclusively to the Moluche or Nguluche from Araucanía) inhabited the valleys between the Itata and Toltén Rivers, as well as the Huilliche (people of the South), the Cuncos.
In the seventeenth and eighteenth centuries the Mapuches expanded eastward into the Andes and pampas forming with the existing people the Poyas and Pehuenche. At about the same time ethnic groups of the pampa regions, the Puelche, Ranqueles and northern Aonikenk, called Patagons by Ferdinand Magellan, known now as Tehuelche, made contact with Mapuche groups, adopting their language and some culture (in what came to be called the Araucanization).