Final answer:
The tribes in the southeast were affected by the Civil War through displacement, confinement to reservations, and assimilation efforts.
Step-by-step explanation:
The tribes in the southeast were significantly affected by the Civil War. Many Native American tribes, known as the Five Civilized Tribes, supported the Confederate States of America (CSA) and even sent delegates to the Confederate Congress.
After the war, the tribes found themselves displaced once again and confined to reservations that were often poor and unable to sustain their traditional ways of life. They became dependent on the Bureau of Indian Affairs (BIA) for support and were subjected to assimilation efforts, including forcing Indian children to attend boarding schools.
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