Polygamy in the Church of Jesus Christ of Latter Day Saints, or plural marriage, is generally believed to have originated with the founder of Mormonism, Joseph Smith. According to several of his associates, Smith taught that polygamy was a divine commandment and practiced it personally, by some accounts marrying more than 30 women, some of whom had existing marriages to other men. Evidence for Smith's polygamy is provided by the church's "sealing" records, affidavits, letters, journals, and diaries. However, until his death, Smith and the leading church quorums denied that he preached or practiced polygamy. Smith's son Joseph Smith III, his widow Emma Smith, and the Reorganized Church of Jesus Christ of Latter Day Saints (RLDS Church, now called Community of Christ) challenged the evidence and taught that Joseph Smith had opposed polygamy. They instead claimed that Brigham Young, the head of the Church of Jesus Christ of Latter-day Saints (LDS Church), introduced plural marriage after Smith's death. In 1852, leaders of the Utah-based LDS Church publicly announced the doctrine of polygamy.
1830s: origins
When polygamy was introduced into the Latter Day Saint movement is uncertain.
Possible revelation in 1831
Some scholars believe that Smith transcribed a revelation recommending polygamy on July 17, 1831. This revelation is described in a letter to Brigham Young written in 1861 by an early Mormon convert, William W. Phelps, thirty years after the revelation was said to be given. This was during a period when LDS Church leaders were justifying the practice and origins of plural marriage, particularly to Mormon splinter groups who did not agree with the practice.
The key portion of the revelation proclaims:
This wording is comparable with the portion of the 1830 edition of the Book of Mormon, which corresponds to today's 2 Nephi 30:5–6, which states that when Lamanites and Nephites receive the gospel they will become a "white and a delightsome people." Unlike the 1831 revelation, the 1830 version of the Book of Mormon does not specify that the Native Americans would become "white and delightsome" through plural marriage. A note from Phelps in the same document explains how the conversion of the Native Americans coincided with Smith's plan for a new system of marriage:
A reference was made to this revelation five months after its alleged date in a letter by Mormon apostate Ezra Booth to the Ohio Star on December 8, 1831, in which he refers to the "revelation [that the Mormon Elders] form a matrimonial alliance with the Natives", but the letter makes no reference to polygamy. This letter is significant in that it confirms that a revelation about marrying Natives occurred, but it is also problematic for multiple reasons. One is the context for the revelation. Mormon missionaries had been denied access to the Indian Territory as they lacked authorization from the US Indian Agents. They sought access multiple times and were never granted permission. To circumvent this, they were to get a license from the government to trade goods with the Indians and while trading "disseminate the principles of Mormonism among them." In addition to the trading license, marrying the Natives would be an additional means of circumventing the US Indian Agents. Finally, had the revelation mentioned polygamy, Booth would likely have mentioned it as it would further his anti-Mormon agenda.
The LDS Church never published Phelps's note or letter, nor has it been canonized as part of Mormon scripture, which was done with many of Smith's other revelations. In 1943, historian Fawn Brodie stated that LDS Church historian Joseph Fielding Smith told her that a revelation foreshadowing polygamy had been written in 1831 but never published, and that although its existence in the church library is acknowledged, "in conformity with the church policy", Brodie would not be permitted to examine it. Three authors assert that a second record of the revelation exists, believed to be in the LDS Church's historical department, though its existence has not been confirmed by the church.
Though the 1831 revelation is cited by Mormon historians, non-Mormon historians, and critics, there are dissenting opinions, and no consensus has been reached.
Early teachings and practice
After Smith's death, many early converts, including apostles Brigham Young, Orson Pratt, and Lyman E. Johnson, said that Smith was teaching plural marriage as early as 1831 or 1832. Mary Elizabeth Rollins Lightner, Smith's ninth wife claimed that Smith had a private conversation with her in 1831 when she was twelve.