Answer: Settlers and tribes both had effects on each other. On many trails headed west, settlers traveled in fear of attack from tribes who would rob or kill members of caravans. Tribes would attack stagecoaches and wagons that traveled across their lands. On the other hand, settlers constantly encroached on tribes’ lands. When settlers drove cattle, built railroads, established trails, and created new settlements, tribes were driven off of their lands. Often, this happened to tribes that had already relocated from other parts of the country to escape settlement. As the two groups fought over land, tribes struggled to get the resources they needed. While both groups profited from each other, both also were harmed by expansion in different ways.