The Church of Jesus Christ of Latter-day Saints, more commonly known as the Mormon church to most who are not members of the church, is the largest denomination originating from the Latter Day Saint movement founded by Joseph Smith in Upstate New York in 1830.
Adherents, often referred to in-game as New Canaanites, view good works and adherence to the teachings of Jesus Christ as revealed through Joseph Smith, Jr. as the central tenets of their religion. The Church has an open canon which includes five scriptural texts: the Bible (both Old and New Testaments), the Book of Mormon, the Doctrine and Covenants, and the Pearl of Great Price. Other than the Bible, the majority of the LDS canon consists of revelation dictated by Joseph Smith (who was subsequently murdered by an angry mob) and includes commentary and exegesis about the Bible, texts described as lost parts of the Bible, and other works believed to be written by ancient prophets. The Church of Jesus Christ of Latter-day Saints also follows a path of modern revelation, with each successive president of the church (and his Apostles) being sustained as prophets, seers, and revelators ; church publications and talks from General Conference are often likened to scripture, and are used as such in a supplementary fashion.
Groups of Mormons still survive in the wasteland, mostly in the area that used to be known as the state of Utah, which originated as a safe haven for the Latter-day Saints as they migrated to escape persecution. The Mormon Pioneers succeeded in establishing a community, which became Salt Lake City, Utah's capital and most populous city. Some time after a direct war with the United States, the Utah territory, also known to the Mormons as Deseret, became the state of Utah in 1896. This turn of events occurred after a series of unsuccessful petitions by the Church's former president, Brigham Young, who had also been Utah territory's first governor. The petitions had been denied in the past, primarily due to the Church's early stance on polygamy. After the proclamation of the 1890 Manifesto (which denounced any future plural marriages) by Church president Wilford Woodruff, Utah was granted statehood.
Though truly brutal groups like Caesar's Legion will not hesitate to enslave or kill Mormons, most tribals and other organizations leave the Mormons alone, knowing that they often will voluntarily give medicine or other aid to groups who need it. Wastelanders tolerate the Mormons' proselytizing because finding help with relatively benign conditions is rare; the New Canaanites are also known as fair traders.
In 2062, many Mormon congregations came together to purchase spots in Vault 70, located in Salt Lake City, Utah. As part of the vault experiment, Vault 70 was assigned a clandestine social experiment―specifically, for the jumpsuit extruders to fail within six months of the vault's sealing. The eventual total lack of clothing combined with Mormon religious sensibilities resulted in the single largest block of social data collected during the vault program.
The following is based on Van Buren and has not been confirmed by canon sources.
In 2190, 113 years after the Great War, Vault 70 opened and its residents used the three G.E.C.K.'s within to finally realize Joseph Smith's dream of a New Jerusalem, atop the ruins of Salt Lake City. Between 2220 and 2233, New Jerusalem's intolerant prophet and apostles repeatedly voted to have no commerce with outsiders from other, failed communities, refugees, or tribals. Finally, in 2233, many disgruntled and desperate refugees stormed New Jerusalem's gates and overwhelmed the militia, certain the Mormons were hoarding food and water while everyone outside the city walls suffered and died. Most of the Mormons were slaughtered and those that survived scattered into the desert.
Two years after the fall of New Jerusalem, the new living prophet, Judah Black, led most of the survivors of the Mormon community north to Ogden. There, they established the town of New Canaan. A year later, they and a group of squatters fixed the Jericho water plant to run fresh water into the city. Judah Black died of old age in 2245, and within two years, Jeremiah Rigdon emerged from a strange and powerful fever, claiming that an angel appeared to him in a vision, calling him to be the living prophet of God.
In 2246, the Mormon missionary Joshua Graham encountered two Followers of the Apocalypse: Bill Calhoun and Edward Sallow. The three eventually went on to become the founders of Caesar's Legion, bringing great shame to the Mormons. Following Graham's defeat after the First Battle of Hoover Dam, the church accepted him back into the flock, a decision that incurred the wrath of Sallow, now known as Caesar. In 2281, New Canaan was burned to the ground by the White Legs–a group of tribals who were tasked with the destruction of all of Graham's people as part of their petition to be absorbed into the Legion—killing Bishop Mordecai in the process. 30 of the survivors managed to find each other in the chaos, and traveled to Zion Canyon under the leadership of Daniel. There, they encountered 4 tribes - the Crazy Horns, the Dead Horses, the Sorrows and the Tar Walkers. By the time the Courier arrives in Zion, only the Dead Horses and the Sorrows remain (the other two having fallen already to the White Legs). Daniel and Graham see it as their responsibility to ensure the survival of the native tribes by any means necessary.
I think Mormons are interesting because they occupy such a unique position in American society. Since their early days, they've had a lot of conflicts with the people around them and rapidly pushed west, out of the Midwest, and eventually into what would become Utah. Events like Missouri Executive Order 44, Haun's Mill, and the Mountain Meadows Massacre show how violent that conflict could be at times. The society that they built in the Utah region was done with local tribes like the Paiute but apart from outside, mostly-European influences.
As a result of these conflicts and their eventual concentrated build-up of Utah, Mormons have been, and often still are, considered "other" by many Americans. Unsurprisingly, Mormon communities can be extremely organized and powerful. Unlike many other powerful religious groups, the geographic concentration of Mormons is quite dense, so I think it produces an interesting dynamic in American politics and culture. The military history of the Mormons (fighting against and for the federal government) and the central role of J.M. Browning in the development of many of the U.S. military's most notable weapons (the BAR, M1911 Pistol, and M2) throws another element into the mix.
↑Joseph Fielding Smith, ed. Teachings of the Prophet Joseph Smith (1976) p. 121 ("The fundamental principles of our religion are the testimony of the Apostles and Prophets, concerning Jesus Christ, that He died, was buried, and rose again the third day, and ascended into heaven; and all other things which pertain to our religion are only appendages to it.").