Answer: Railroad
Native American tribes had already been struggling for decades before the construction of a railroad began to be planned. However, the railroad was a catastrophic event for the Natives' way of life. The railroad forever altered the landscape of their traditional land, as well as caused the disappearance of wild game, such as bison. This was particularly destructive to the Plains people, who depended on the bison for nearly all of their needs.
The railroad also increased conflict between the Native people and the colonizers. It allowed white settlers to move to areas originally only inhabited by Native tribes, causing land disputes, deaths and displacement.
