As early in American history as 1824 and until 1835, trappers and fur traders such as Jim Bridger engaged in the flourishing transaction of trapping and hunting furs in Cache Valley. It is believed that these mountain men dug fur “caches” on the banks of the Little Bear River, storing large quantities of furs and pelts. Trappers found an abundance of prey, especially beaver, along the banks of the slow-moving Bear River and Little Bear River.

General William Ashley developed the concept of “rendezvous” in order to keep trappers out in the field instead of having to travel to established forts or trading posts to re-supply. In 1825 the first rendezvous was held and continued yearly until 1840, with Willow Valley (Cache Valley) hosting the 1826 July rendezvous. At that time the average price for beaver was approximately $3.00 per pound. The Trade and Intercourse Act of 1790 dictated that in order to trade furs, a license must be obtained by an established and maintained permanent trading post. Accordingly, the mountain men built Fort Defiance for the 1826 gathering, a settlement of log cabins and brush shelters to satisfy the license requirements and serve as winter quarters for trappers. The rendezvous was also held in Cache Valley in the late summer of 1831.

During Brigham Young’s initial colonizing activities in Utah Territory, he considered Cache Valley unpromising due to reports of early autumn and late spring frosts and the severe winters of its climate and potential Indian hostilities. However,at the suggestion of knowledgeable mountain men who were aware of the area’s rich grasslands and abundant supply of water, Young sent scouts to find a suitable location for a northern settlement in 1856. The men reached the valley during the summer, and upon entering found grasses that were excellent both for grazing and harvesting for winter stock feed. They toured the valley immediately to determine the most favorable location for a settlement and selected the south part of the valley.