Upvote:2
As the Mapuche sit in the first rank in terms of indigenous resistance they must have already had a developed practice of war when the Inca arrived. However, they did not wield this power as a state. According to the Encyclopedia of the Stateless Nations, "Although they dominated a vast territory, the Pre-Columbian Mapuches did not recognize any political or cultural entity above the village level". Wars between the "villages" were settled locally, and definitely most of these episodes are lost to history.
Insofar as the Mapuche are prominent today, they outcompeted and outlasted other local groups. That this process occurred is suggested by the disagreement over the linguistic classification of Mapudungun. It would be shocking if the growth of the Mapuche nation occurred without the use of violence.
Even as Mapuches defended some piece of territory from an invading army, they lost another, likely prompting conflict between the communities forced to retreat and those nearby. Some smaller groups may also have been hit disproportionately hard by introduced disease. Centuries of these colonial pressures gradually depleted the diverse groups, making their members prone to give up their own heritage and join another tribe with a viable population (either voluntarily or not). The Museo Chileno de Arte Precolombino confirms that "the arrival of the Spanish in the 16th Century seems to have triggered the amalgamation of several indigenous groups and the forging of closer social and cultural ties, all of which is part of what we know today as the history of the Mapuche identity."
So yes, Mapuche people knocked over communities of other tribes, but no, there was no grand Mapuche conquest.