What became known as the Mormon Trail is a route that travelers west took from Illinois to modem Utah. This migration contributed to the growth of Salt Lake City.

The association of the route with Mormons begins after 1844, when Joseph Smith, the founder of the Church of Jesus Christ of Latter-day Saints, was killed. As their Nauvoo, Illinois location seemed dangerous, they decided to relocate. Led by Brigham Young, who succeeded Smith, they began the move in 1846.

Ultimately, thousands of Mormons used the route along established trails, setting up winter camps along the way. The route went through Iowa, Nebraska, and Wyoming, where it largely followed the primary route, the Oregon Trail. Splitting to turn south, it continued to the outpost on the Great Salt Lake.