Origin of Latter Day Saint polygamy

Polygamy, or plural marriage, in the Church of Jesus Christ of Latter Day Saints probably originated with the founder of Mormonism, Joseph Smith, who taught that polygamy was a divine commandment. Smith practiced it personally, by some accounts marrying more than 30 women some of whom had existing marriages to other men. Evidence for Smith's position is provided by the church's "sealing" records, public marriage licenses (in many cases notarized), affidavits, letters, and 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 the 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 acknowledged that Smith taught and practiced polygamy.

When polygamy was introduced into the Latter Day Saint movement is uncertain.

Some scholars believe that Smith transcribed a revelation recommending polygamy on July 17, 1831. This alleged revelation is described in a letter to Brigham Young written in 1861 by an early Mormon convert, William W. Phelps, thirty years after the supposed revelation. 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.

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