Because buffalo were such big animals they could feed a lot of people and many of their parts came to use such as their hides and horns
Disease is the answer I believe... If not than it is death by war or massacre
Pioneer settlers were sometimes pulled west because they wanted to make a better living. The biggest factor that pulled pioneers west was the opportunity to buy land.
Manifest destiny was caused by the fact that the American people were historically connected to English civilization, this gave them a sense of superiority over the other peoples who lived in North America. Because of the fact that they were white and civilized, the Americans felt superior to the Indians.
Suffrage is the right to vote in political elections