How did the Civil War affect Indian Territory?

During the Civil War, both the Union and Confederate sides considered Indian Territory of great importance because of its potential for controlling lands west of the Mississippi and its position as a buffer between the free state of Kansas and slaveholding Texas. Both sides courted the support of the tribes living in Indian Territory. Some of the tribes leaned toward the north since there were treaties placing them under the protection of the United States. Many, however, held slaves pushing those groups toward the south. The tribes, then, were split in their support and the first battle of the Civil War to reach Indian Territory was the Battle of Honey Springs in the eastern area.

The greatest effect of the Civil War on Indian Territory occurred in the years after the war ended. Since the number of Native Americans supporting the Confederacy far exceeded that of the number supporting the Union, there was considerable feeling that treaties with the tribes were no longer valid. Citing the widespread support for the Confederacy among the tribes, the United States government in 1866 declared all existing treaties with the five nations to be null and void. Seven thousand slaves held by the tribes were freed and much of the land that had been designated for the tribes was reclaimed and eventually opened for settlement and subsequent statehood.

Explanation:

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Answer

The war brought an end to the era of tribal ranching

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