Fremont County is located in the easternmost part of central Idaho. The county seat is St. Anthony. The 2010 census counted 13,242 residents. Fremont County was created in 1893 and named for Major John C. Fremont, "the Pathfinder." The first Anglo-European to visit is thought to have been John Colter, the mountain man that broke off from the returning Lewis and Clark expedition in 1808 to start trapping for fur in the region. Andrew Henry and a party of trappers associated with his Rocky Mountain Fur Company wintered in what was to become Fremont County in 1810-1811. (The North Fork of the Snake River was named for Henry.) Over the next few decades of the nineteenth century, fur trappers roamed over the land and periodic conflict with Indians brought various military excursions through the area.
When Anglo-Europeans arrived in what is today Fremont County, the countryside was the home of the Shoshone and Bannock Indian Tribes. These were, at the time, two separate tribes that traded with each other and with other tribes in the region. In 1878, the so-called Bannock War took place. Brigadier General Oliver O. Howard led a mixed army/militia force against a contingent of Bannock and Paiute Indians led by Chiefs Buffalo Horn and Egan. As a result of their defeat in this conflict, the Bannock were forced onto the Fort Hall Reservation. Shoshone Indians were also made to live there. Today, the federal government recognizes the Bannock-Shoshone Tribe.
During the nineteenth century, a few of the mountain men built cabins in various parts of the county, but settlement was generally thin until the end of the century when cattle ranching and agriculture were introduced. Homesteading in and around Egin Bench starting in 1879 is generally credited as being the first actual settlement. Mormon immigration into this region at this time appears to have contributed greatly to the growth of the settlements. Yellowstone National Park, part of which is in Fremont County, was established in 1872 and the county offered access to the Western Entrance. The railroad arrived in 1906. The tourist industry was introduced early with park visitors taking the train to the end of the line (Ashton) and transferring to sightseeing wagons and buggies.