member of any of several denominations that trace their origins to a religion founded by Joseph Smith, Jr. (Smith, Joseph) (1805–1844), in the United States in 1830. The term Mormon, often used to refer to members of these churches, comes from the Book of Mormon, which was published by Smith in 1830. Now an international movement, Mormonism is characterized by a unique understanding of the Godhead, emphasis on family life, belief in continuing revelation, desire for order, respect for authority, and missionary work. Mormons also obey strict prohibitions on alcohol, tobacco, coffee, and tea and promote education and a vigorous work ethic.

The Church of Jesus Christ of Latter-day Saints, the principal formal body embracing Mormonism, is headquartered in Salt Lake City, Utah, and had more than 11 million members by the early 21st century. About 50 percent of the church's members live in the United States and the rest in Latin America, Canada, Europe, Africa, the Philippines, and parts of Oceania. The next-largest Mormon denomination, the Community of Christ (until 2001 the Reorganized Church of Jesus Christ of Latter Day Saints), is headquartered in Independence, Mo., and had a membership of approximately 250,000 in the early 21st century.

The new church was millennialist (millennialism), believing in the imminent Second Coming of Christ and his establishment of a 1,000-year reign of peace. This belief inspired Smith's desire to establish Zion, the kingdom of God, which was to be built somewhere in the western United States. He received revelations, not only of theological truth but also day-to-day practical guidance. The Mormons devised new secular institutions, including collective ownership (later changed to a system of tithing) and polygamy, which was practiced by Smith himself and by most leading Mormons in the church's early years.

Soon after the church's founding, Smith and the bulk of the members moved to Kirtland, Ohio, where a prominent preacher, Sidney Rigdon (Rigdon, Sidney), and his following had embraced Mormonism. In Jackson county, Mo., where it was revealed that Zion was to be established, Smith instituted a communalistic United Order of Enoch. But strife with non-Mormons in the area led to killings and the burning of Mormon property. Tensions between Mormons and local slave-owning Missourians, who viewed them as religious fanatics and possible abolitionists, escalated to armed skirmishes that forced 15,000 Mormons to leave Missouri for Illinois in 1839, where Smith built a new city, Nauvoo. There the Mormons' commercial success and growing political power once again provoked renewed hostility from their non-Mormon neighbours. Smith's suppression of some dissidents among the Nauvoo Mormons in 1844 intensified non-Mormon resentment and furnished grounds for his arrest. Smith and his brother Hyrum were murdered by a mob while both were in jail in Carthage, near Nauvoo, on June 27, 1844.

After Smith's unexpected death, the government of the church was left in the hands of the Council of the Twelve Apostles, whose senior member was Brigham Young (Young, Brigham). Ignoring several claimants to the church leadership, the majority of Mormons supported Young, who became the church's second president. Increasing mob violence, however, made the Mormons' continued presence in Nauvoo untenable, and Young thus led a mass 1,100-mile (1,800-km) migration (human migration) to Utah in 1846–47. There the Mormons hoped to establish a commonwealth where they could practice their religion without persecution. Envisioning a new state that he called Deseret, Young helped to establish more than 300 communities in Utah and neighbouring territories. To build the population, he sent missionaries across North America (United States) and into Europe. Converts were urged to migrate to the new land, and it is estimated that about 80,000 Mormon pioneers traveling by wagon, by handcart, or on foot had reached Salt Lake City by 1869, when the arrival of the railroads made the journey much easier.

Despite the obstacles presented by the desert area of the Great Basin, the pioneers made steady progress in farming, partly through their innovative methods of irrigation. Their petition for statehood in 1849 was denied by the U.S. government, which instead organized the area as a territory, with Young as its first governor. Future efforts to gain statehood were blocked by the announcement in 1852 of the church's belief in polygamy, a practice that had begun quietly among the church leaders during the Nauvoo period. Conflicts between Young and federal officials over this practice and over Mormon attempts to establish a theocratic government continued during the 1850s. Tensions increased following the 1857 Mountain Meadows massacre, in which a group of Mormons killed members of a wagon train passing through the region. In response to the conflicts with federal officials, U.S. Pres. James Buchanan (Buchanan, James) dispatched a military expedition to Utah to suppress the Mormon “rebellion” and to impose a non-Mormon governor, Alfred Cummings, on the territory. Fearing that the purpose of the expedition was to persecute the Mormons, Young called on the Utah militia to prepare to defend the territory. A negotiated settlement was reached in 1858, and Cummings, the new governor, eventually became popular with the Mormons. Although the abortive military episode, later known as “Buchanan's blunder,” aroused widespread public sympathy for the Mormons, it succeeded in ending direct Mormon control of Utah's territorial government.

After his death in 1877, Young was succeeded by John Taylor, the senior member of the Council of the Twelve Apostles. During Taylor's presidency, the U.S. government intensified its campaign against polygamy. In 1890 Taylor's successor, Wilford Woodruff (Woodruff, Wilford), announced the church's abandonment of the practice in order to conform with U.S. law, and in 1896 the territory of Utah was admitted into the union as the 45th state. However, Woodruff's pronouncement, theManifesto, forbade polygamy only in the United States, and for a decade or so it continued in Mexico and other places outside the U.S. government's jurisdiction.

In the history of Mormonism, more than 150 different independent groups have formed to follow new prophets, to defend polygamy, or to continue other practices that were discarded by the mainstream Mormon churches. An important minority of Mormons, for example, rejected Young's leadership and remained in the Midwest. The largest of these groups, which gained the cooperation of Smith's widow Emma and his son Joseph Smith III (Smith, Joseph, III), formed the Reorganized Church of Jesus Christ of Latter Day Saints (Community of Christ) (now known as the Community of Christ) in 1852–60. The Reorganized Church eventually settled in Independence, Mo., which Smith had designated as the location of Zion.

Many smaller splinter groups also arose after Smith's death. One faction moved to Independence and purchased the so-called Temple Lot, the site chosen by Smith for the new temple. The possession of this valued property embittered relations with the Reorganized Church, whose headquarters are on land immediately to the south. Other factions that rejected Young's leadership also appeared. Rigdon led one, and Apostle Lyman Wight took another to Texas. David Whitmer and Martin Harris, two early converts who, along with Joseph Smith, testified that they saw the golden plates and the angel Moroni, eventually set up a church in Kirtland. In 1847 James Jesse Strang (Strang, James Jesse) established a polygamous community of about 3,000 people on Beaver Island in Lake Michigan whose members became known as Strangites.

Among the most significant of Latter-Day Saints factions to emerge in the 20th century were groups that practice polygamy. The first such colony was established at Short Creek (now Colorado City), just south of the Utah border in northwestern Arizona, in 1902, shortly after the Church of Jesus Christ of Latter-day Saints imposed excommunication as the penalty for entering into or officiating over a plural marriage; additional colonies were later founded in Mexico and Salt Lake City. Church and federal authorities have attempted to stamp out the polygamy-practicing groups, which nevertheless claim a membership of more than 30,000.

The Community of Christ uses Smith's unfinished translation of the Bible, which incorporates prophecies of his own coming and of the Book of Mormon. The church in Utah, however, prefers the King James Version. Of great importance to all Latter-day Saints is the Book of Mormon, which recounts the history of a group of Hebrews, led by the prophet Lehi, who migrated from Jerusalem to America about 600 BCE. There they multiplied and split into two groups: the virtuous Nephites, who prospered for a time, and the hostile Lamanites, who eventually exterminated the Nephites.

Other revealed writings, including Smith's translation of “Egyptian” texts that he declared to be the Book of Abraham, were incorporated into the Pearl of Great Price. The Doctrines and Covenants contains Smith's ongoing revelations through 1844. The editions of the Utah church and of the Community of Christ add the revelations of their respective church presidents (who, like Smith, are regarded as prophets). The Community of Christ's version of the Doctrines and Covenants omits several of Smith's revelations that appear in the Utah edition.

Mormons believe that faithful members of the church may receive God's fullness and thus become gods themselves. Everyone who ever lived, save for a few who reject God having known his power, will receive some degree of glory in the afterlife. At Christ's return to earth, he will establish a millennial kingdom. After the millennium, the earth will become a celestial sphere and the inheritance of the righteous. Others will be assigned to lesser kingdoms named terrestrial and “telestial.”

Mormons regard Christian churches as apostate for lacking revelation and an authoritative priesthood, although they are thought to be positive institutions in other respects. Smith, they believe, came to restore the institutions of the early Christian church. Although calling people to repent, Smith's creed reflected contemporary American optimism in its emphasis on humanity's inherent goodness and limitless potential for progress.

The Utah branch of Mormonism dissolves the distinctions between the priesthood (priest) and the laity. At age 12, all worthy males (a category which until 1978 generally did not include black men) become deacons in the Aaronic priesthood; they become teachers at age 14 and priests at age 16. About two years later they may enter the Melchizedek priesthood as elders (elder), and thereafter they may enter the upper ranks of the church priesthood hierarchy. In addition to service in the priesthood, many Mormons accept the call to missionary work. Young men, generally between the ages of 19 and 21, undertake a 24-month proselytizing mission, as do young women of age 21 and older. Many older married couples serve as missionaries for 18 months. This missionary work has helped to make Mormonism one of the fastest-growing religions in the world.

Baptism, a rite signifying repentance and obedience, is administered to children at age eight and to adult converts. Baptism is understood as essential for salvation and has acquired additional importance because it may be undertaken by proxy for those who died without knowledge of the truth. The Mormons' interest in genealogy proceeds from their concern to save the deceased population of the earth. Baptism for the dead, endowment (a rite of adult initiation in which blessings and knowledge are imparted to the initiate), and the sealing of husbands, wives, and children (which may also be undertaken by proxy for the dead) are essential ceremonies that take place in the temple. During the endowment, the person is ritually washed, anointed with oil, and dressed in temple garments. This is followed by a dramatic performance of the story of creation, the Fall, and the return of God.

At the local level, members of the church are divided into “stakes” of 4,000 to 5,000 members under stake presidents and into wards, each of a few hundred members, under a bishop. The religious life of each member is focused on the ward, through which religious, economic, and social activities, tithing, and the operation of the church's elaborate welfare plan are organized.

The Community of Christ, which was known as the Reorganized Church of Jesus Christ of Latter Day Saints until 2001, holds less firmly to the Book of Mormon than its sister church and rejects various teachings, especially baptism on behalf of the dead and tithing. It never practiced polygamy or sealing for the afterlife. It does not perform temple ceremonies at the Kirtland, Ohio, temple, which it owns, or at the temple in Independence. The office of church president was for many years passed to lineal descendants of Joseph Smith III. With the end of the presidency of Wallace B. Smith in 1996, however, no Smith descendant was available to take the reins of leadership. In that year, the church's World Conference chose W. Grant McMurray as its new president.