How did US get Utah?

Answer 1

In 1844 following the assignation of the Latter Day Saint prophet over 11,000 Mormons made the trek to the unincorporated land we know as Utah today to avoid persecution in Illinois. The Mormons named the land Deseret and were annexed into the Union from Mexico as the Utah Territory in 1850 as a result of the Mexican-American War. Utah was not granted statehood until 1896 as a result of the LDS practice of polygamy (having multiple wives) the U.S. government would not admit Utah until the practice was stopped.