 To provide a local government structure, the State of Deseret legislature created the county on January 31, 1850, although it was not organized until January 17, 1851, with description stretching from the future Colorado, across Utah, and into the future Nevada.It was named "Little Salt Lake County" at creation, but on December 3, 1850, a legislative act changed its name to Iron County.Its borders were altered in 1850, 1852, 1854, 1856, and 1861.