The Mormon pioneers were run out of Ohio by mobs, forced out of Missouri by government extermination order, and told to leave Illinois by the government. They appealed to the US president for help, who told them he could do nothing for them, so they left the United States for Mexico. A couple years later, the area where there were living became part of the United States.
Brigham Young
Brigham Young
Brigham Young. The 2nd president of the church.
Utah.
In 1844 the Mormons followed Brigham Young to what would become the Utah Territory.
in present-day Utah
Brigham Young lead the first group of Mormon Pioneers to Utah Territory (which was then Mexico) in 1847.
Brigham Young led the Mormons out of Illinois in a mass exodus to present-day Utah.
Brigham Young did not start any religions. He was the second leader of the Church of Jesus Christ of Latter-day Saints (the "Mormon" church) which was founded by Joseph Smith, Jr. He led the Mormons from Illinois to Utah after Joseph Smith was murdered.
The Mormon Pioneers travelled to Utah in dozens of small groups over a period of about 20 years. Each one of these small groups had their own leader, generally a young man in his 20's or 30's who had prior experience on the trail or in the west. Overall, Brigham Young is the one who directed them to move to Utah, and Mormons believe that Brigham Young was led by God to the exact place where they would first settle in Salt Lake City.
Brigham Young became a leader of the Mormoms and led the religious group to settle in Salt Lake City. Utah was not yet a US State. In 1848, Utah was ceded to the USA from Mexico.
Members of the Church of Jesus Christ of Latter-day Saints (commonly called the "Mormon" church) faced extreme persecution and violence in the east and Midwest, so they went further west in search of a place where they could practice their religion in peace.