How did the discovery of gold influence events leading up to chief Joesph's war

The discovery of gold and mining on the West led to a railroad boost as more and more people were moving there in the hopes of becoming rich. The growth the West was experiencing ultimately led to the Federal Government pressuring the Nez Perce (natives of Wallowa Valley) to give up their homeland to them. Natives followed their tribe leader, Chief Joseph, and refused to be forced onto a reservation, so they walked for 1400 miles attempting to reach Canada, but meeting their sad end when they encountered the US Army and battled them in the Nez Perce War.