The demand for beaver pelts in the early 1800s led to the exploration and eventual settlement of the American West. South Pass was part of a major thoroughfare through the Rockies and its discovery is significant to the era known as the fur trade.
South Pass was first crossed by white men in 1812. The Astorians, a small party of American Fur Company trappers led by Robert Stuart, used it as they traveled east with dispatches for company owner, John Jacob Astor. Even though Stuart noted South Pass in his diary and word of his journey was printed in a Missouri newspaper, it would be another decade before white men "rediscovered" it.
For Jedidiah Smith and other mountain men working for entrepreneur William Ashley in the winter of 1823-24, the rugged Wind River Range in front of you was a barrier between them and the beaver-rich Green River Valley further west. Failing to negotiate these mountains through Union Pass further north, Smith and his men finally reached the Green River by traversing the southern end of the range at this gradual incline. Traveling west with supplies in 1825, Ashley initiated the Rendezvous, an annual event lasting until approximately 1840 when the demand for beaver played out.