By Allen C. Guelzo, Princeton University
The Adventists, initially called the Millerites, organized themselves around William Miller. Based on the teachings of Miller, that Jesus would return, literally, to the Earth in 1843, the Millerites were not so much a separate sect like the Shakers as they were a movement of enthusiasts across many denominations.

The Millerite Faith
The Millerites were united by the single conviction that William Miller was right, and that the world would end with the Second Advent of Christ, on March 21, 1843.
This belief earned Miller and his followers very little respect and very little affection from organized denominations and the clergy. By 1843, the movement was already starting to harden into its own separate denomination. It hardened still more when, after devoted Millerites spent the evening of March 21, 1843, standing out on the hills to welcome Jesus—some of them wearing ascension robes, others having given away their property. Jesus did not appear.

Formation of the Adventists
A quick revision of Miller’s calculations fixed a new date for April 18, then for March 21, 1844, and then finally for October 22, 1844. By that time, the Millerites had become a laughing stock, and so no more dates were set.
The laughter only caused the Millerite faithful to dig their heels in more deeply, and by 1844, William Miller himself sanctioned the organization of his band as an entirely new denomination, the Adventists. They explained the great disappointment as no disappointment at all. In fact, they taught, Christ had returned but metaphorically and in spirit, rather than in flesh.
By 1863, the Adventists had organized 125 churches and made themselves somewhat unloved by unceasingly denouncing the American Republic as a corrupted whore that God would destroy in the flames of the Book of Revelation.
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The Book of Mormon
However, the most extreme brand of come-outerism came in the form of Mormonism. In the spring of 1830, Joseph Smith published the Book of Mormon. It claimed to be a translation made by Smith of a long lost book engraved on plates of gold, which he had been ordered to unearth by an angel named Moroni from a hill near Palmyra, New York.
The plates told the story of three tribes of ancient Israelites who had crossed the Atlantic, and were rewarded in America with their own special visitation from Jesus Christ. These tribes eventually went to war with each other, with the righteous tribe of Nephites finally reduced only to one man, Mormon, who buried the golden plates telling the story in the hill near Palmyra.
The Church of Jesus Christ of Latter-day Saints
Now, at the very least, the Book of Mormon demonstrated that Joseph Smith was a man of tremendous imagination. He put that imagination to work by organizing his own church, the Church of Jesus Christ of Latter-day Saints, with the Book of Mormon as its principal revelation. The surrounding churches looked pretty dimly on this, and even more dimly when Smith took to attacking them and preaching polygamy doctrines.
Making himself unwelcome on both counts, Smith turned his new church into an autonomous community in Ohio and then, when civil prosecution began catching up with them, to a new settlement in Nauvoo, Illinois. Smith was eventually arrested, and then lynched in 1844.
The Come-outer Sects
However, in 1847, Smith’s successor, Brigham Young, as the leader of the Latter-day Saints, lifted the Nauvoo community almost single-handedly, and moved them to the shores of the Great Salt Lake, where they flourished, and remain flourishing to this day, with something over six million members worldwide.
What tied together these come-outer sects was their short-term pessimism about the corrupt society around them; that was why they had to withdraw from them, but also their long-term optimism about the ease of founding new Jerusalems in America.
It is one measure of how deep this religious impulse ran that even secular reform movements, calling for a rethinking of American participation in the world of market capitalism—or not only capitalism but education, diet, and women’s rights—pursued almost exactly the same trajectory of pessimism and optimism.
If the main impulse of religious reform was the fear of moral corruption, then the driving force of the secular reform movements was the fear of political and economic corruption. These movements included Thomas Skidmore’s workingmen’s party in New York in 1829, which called for a civil revolution to: “…assure every human being an equal amount of property on arriving at the age of maturity, and previous thereto equal food, clothing, and instruction at the public expense.”
Common Questions about the Rise of Adventists and Mormons
A revision of William Miller‘s calculations first fixed a new date for for the Second Advent of Christ for April 18, then for March 21, 1844, and then October 22, 1844. By that time, the Millerites had become a laughing stock, and so no more dates were set.
By 1844, William Miller himself sanctioned the organization of his band as an entirely new denomination, the Adventists.
In the spring of 1830, Joseph Smith published the Book of Mormon, which claimed to be a translation made by Smith of a long lost book engraved on plates of gold, which he had been ordered to unearth by an angel named Moroni from a hill near Palmyra, New York.