Although according to the 2002 census there were just 600,000 mapuches in the country, the current estimation is bigger, with about 1.5 million identified as part of the mapuche people. Another important thing is that most of the mapuche population actually live in Santiago, specially in the working class communes as Pudahuel, Cerro Navia, La Pintana, Maipu, La Florida and Peņalolen (although they represent a higher share of the population in the Araucania Region).
I believe that most of the country population is of mapuche descent (mestizos).
PD: This is the mapuche flag