Final answer:
The Bozeman Trail was closed due to battles between Native American tribes and settlers, particularly the Sioux.
Step-by-step explanation:
The Bozeman Trail was closed because of the Sioux winning battles and forcing the government to send a peace commission who agreed to close it.
This decision was a result of the conflicts between the Native American tribes, particularly the Sioux, and the settlers on the trail.
The Sioux were resisting the influx of settlers and demanded the closure of the trail which had become a major route to the goldfields in Montana. The peace commission agreed to their demands and closed the trail.
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