 Archaeological evidence indicates that human habitation in Idaho began towards the end of the last ice age : bone fragments about 10 @,@ 000 years old have been found in Wilson <unk> Cave , an <unk> cave on the Snake River Plain believed to have been occupied by indigenous people until as recently as the 17th century . A change of climate around 7000 years ago dried up much of the Great Basin , forcing the Shoshone people northward into the mountainous areas of central Idaho . Most of what is now Boise National Forest was sparsely inhabited by Native Americans , and several archaeological sites , including <unk> , rock shelters , burial grounds , and <unk> have been found along rivers in the area . <unk> and fur traders of European descent first arrived in the area in the early 1800s , starting with John Jacob Astor 's Pacific Fur Company in October 1811 . Donald Mackenzie and <unk> Payette trapped in the area of Boise National Forest in 1819 . By 1840 the fur trade was coming to an end , but the westward migration on the Oregon Trail , which passed south of the forest , was beginning . The first settlers moved into the mountains in the 1860s after gold was discovered in Idaho , which forced many of the Shoshone out and led to conflicts throughout the state , including the <unk> War in southern Idaho . 
