The Bridger Valley grew up in southwestern Wyoming when Jim Bridger, noted frontiersman, and his partner, Louis Vasquez, established Fort Bridger in 1843 to service emigrant traffic. For the next century, the region served as a crossroads for the California/Oregon Trail, the Mormon Trail, the Pony Express Route, the Transcontinental Railroad, and the Lincoln Highway. Today, the valley is a historic byway, incorporating the small towns of Fort Bridger, Urie, Mountain View, and Lyman, which were bypassed when Interstate 80 was built. Bridger Valley Historic Byway is an approximately 20 mile loop showcasing some of Wyoming's most treasured historical sites.

The most notable historic resource in the Bridger Valley remains old Fort Bridger, which is now operated as a state historic park. Established on Black's Fork of the Green River, Bridger and Vasquez planned to trade both with the Indians they had befriended during their years in the fur trade and the westward-bound emigrants. Their first "fort" consisted of two rude double-log houses about 40 feet long, joined by a pen for horses. They also boasted a blacksmith's shop, something that many emigrants welcomed after months on the trails.

But, for those emigrants who had long looked forward to their arrival at Fort Bridger, the post often turned out to be a disappointment. It was not nearly as well-outfitted as the seemingly luxurious Fort Laramie on the eastern Wyoming plains. Fort Bridger turned out to be little more than a crude collection of rough-hewn log buildings. Emigrant Edwin Bryant said of the fort:  "The buildings are two or three miserable cabins, rudely constructed and bearing but a faint resemblance to habitable houses. 

The Mormon Pioneer Company arrived at the fort on July 7, 1847. They spent a day there but found all the prices very inflated. When a small group of Mormons settled nearby, tensions began to mount between Bridger and the new settlers. The settlers reported that Bridger was selling liquor and ammunition to the Indians, in violation of federal law. Brigham Young, a federal Indian agent, responded by sending the Mormon militia to the fort in 1853. Bridger learned they were coming and fled before the Mormons arrived. Later that year, the Mormons established nearby Fort Supply, about twelve miles south, specifically to service the LDS emigration. Bridger complained to General B. F. Butler, a U.S. Senator, claiming the Mormons had robbed him of over $100,000 in goods and supplies and threatened him with death. The next spring, Brigham Young sent well-armed Mormons to take control of both Fort Bridger and the Green River ferries, both of which became integral parts of the Mormon settlement plans for the region. The Mormons build a large stone wal around the fort. Parts of this wall have recently been the subject of archaeological explorations at Fort Bridger.

The Mormons controlled the fort for a year until July 1855 when Bridger returned. They asked him to sell but, seeing the new improvements, Bridger balked. After several months, he finally agreed. But the tensions for the Mormons were far from over. The fort again became embroiled in controversy in the fall of 1857 when the so-called "Utah War" began to heat up. The U.S. Army, under the command of General Albert Sidney Johnston, planned to use Fort Bridger as a base of operations for the move against Utah Territory. But, before they could seize the fort, "Wild Bill" Hickman and his brother burned it and Fort Supply. As a result, Johnston's army spent a miserable winter with little shelter and food.

When the Utah War ended, the U.S. government refused to honor either Bridger's or the Mormon's claim to the property and instead turned it over to William Alexander Carter, who had come west with Johnston's Army as a sutler. Along with his family, Carter lived at the fort, rebuilding and stocking it and eventually becoming Wyoming's first millionaire.