Salt Lake Temple in the context of "Temple Square"

Mormonism is the theology and religious tradition of the Latter Day Saint movement of Restorationist Christianity started by Joseph Smith in Western New York in the 1820s and 1830s. As a label, Mormonism has been applied to various aspects of the Latter Day Saint movement, although since 2018 there has been a push from The Church of Jesus Christ of Latter-day Saints (LDS Church) to distance itself from this label.

A prominent feature of Mormon theology is the Book of Mormon, a 19th-century text which describes itself as a chronicle of early Indigenous peoples of the Americas and their dealings with God. Mormon theology includes mainstream Christian beliefs with modifications stemming from belief in revelations to Smith and other religious leaders. This includes the use of and belief in the Bible and other religious texts, including the Doctrine and Covenants and the Pearl of Great Price. Mormonism includes significant doctrines of eternal marriage, eternal progression, baptism for the dead, sexual purity, health, fasting, Sabbath observance, and formerly, plural marriage.

Brigham Young (/ˈbrɪɡəm/ BRIG-əm; June 1, 1801 – August 29, 1877) was an American religious leader and politician. He was the second president of the Church of Jesus Christ of Latter-day Saints (LDS Church) from 1847 until his death in 1877. He also served as the first governor of the Utah Territory from 1851 until his resignation in 1858.

Young was born in 1801 in Vermont and raised in Upstate New York. After working as a painter and carpenter, he became a full-time LDS Church leader in 1835. Following a short period of service as a missionary, he moved to Missouri in 1838. Later that year, Missouri governor Lilburn Boggs signed the Mormon Extermination Order, and Young organized the migration of the Latter Day Saints from Missouri to Illinois, where he became an inaugural member of the Council of Fifty. In 1844, while he was traveling to gain support for Joseph Smith's presidential campaign, Smith was killed by a mob, igniting the Illinois Mormon War and triggering a succession crisis in the Latter Day Saint movement. After negotiating a ceasefire, Young was unanimously elected as the church's second president in 1847. During the Mormon exodus, Young led his followers west from Nauvoo, Illinois, via the Mormon Trail to the Salt Lake Valley. Once settled in Utah, he ordered the construction of numerous temples, including the Salt Lake Temple. He also formalized the prohibition of black men attaining priesthood and directed the Mormon Reformation. A supporter of education, Young worked to establish the learning institutions that would later become the University of Utah and Brigham Young University.