Why were native Americans forced to assimilate

Cultural assimilation is the process in which a minority group or culture comes to resemble a dominant group or assume the values, behaviors, and beliefs of another group. A conceptualization describes cultural assimilation as similar to acculturation while another merely considers the former as one of the latter's phases. Assimilation could also involve the so-called additive acculturation wherein, instead of replacing the ancestral culture, an individual expands their existing cultural repertoire.

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