The 1890 Manifesto (also known as the Woodruff Manifesto, the Anti-polygamy Manifesto, or simply "the Manifesto") is a statement which officially advised against any future plural marriage in The Church of Jesus Christ of Latter-day Saints (LDS Church). Issued by church president Wilford Woodruff in September 1890, the Manifesto was a response to mounting anti-polygamy pressure from the United States Congress, which by 1890 had disincorporated the church, escheated its assets to the U.S. federal government, and imprisoned many prominent polygamist Mormons. Upon its issuance, the LDS Church in conference accepted Woodruff's Manifesto as "authoritative and binding."

The Manifesto was a dramatic turning point in the history of the LDS Church. It advised church members against entering into any marriage prohibited by the law of the land, and made it possible for Utah to become a U.S. state. Nevertheless, even after the Manifesto, the church quietly continued to perform a small number of plural marriages in the United States, Mexico, and Canada, thus necessitating a Second Manifesto during U.S. congressional hearings in 1904. Though neither Manifesto dissolved existing plural marriages, plural marriage in the LDS Church gradually died by attrition during the early-to-mid 20th century. The Manifesto was canonized in the LDS Church standard works as Official Declaration 1 and is considered by mainstream Mormons to have been prompted by divine revelation (although not a revelation itself), in which Woodruff was shown that the church would be thrown into turmoil if they did not comply with it. Some Mormon fundamentalists rejected the manifesto.

The Church of Jesus Christ of Latter-day Saints, often informally known as the LDS Church or Mormon Church, is a nontrinitarian, Christian restorationist church that considers itself to be the restoration of the original church founded by Jesus Christ. The church is headquartered in the United States in Salt Lake City, Utah, and has established congregations and built temples worldwide. According to the church, it has over 16.6 million members and 51,000 full-time volunteer missionaries. The church is the fourth-largest Christian denomination in the United States, with over 6.7 million members as of 2021 (self reported). It is the largest denomination in the Latter Day Saint movement founded by Joseph Smith during the early 19th-century period of religious revival known as the Second Great Awakening.

Church theology includes the Christian doctrine of salvation only through Jesus Christ, and the substitutionary atonement of Jesus Christ. The church has an open canon which includes four scriptural texts: the Bible, the Book of Mormon, the Doctrine and Covenants, and the Pearl of Great Price. Other than the Bible, the majority of the church's canon consists of material the church's members believe to have been revealed by God to Smith; these include commentary and exegesis about the Bible, texts described as lost parts of the Bible, and other works believed to be written by ancient prophets, including the Book of Mormon. Because of doctrinal differences, Catholic, Orthodox, and many Protestant churches consider the church to be distinct and separate from mainstream Christianity.Latter-day Saints believe that the church president is a modern-day "prophet, seer, and revelator" and that Jesus Christ, under the direction of God the Father, leads the church by revealing his will and delegating his priesthood keys to its president. The president heads a hierarchical structure with various levels reaching down from areas, stakes, to wards. Bishops, drawn from the laity, lead the wards. Male members may be ordained to the priesthood, provided they are living the standards of the church. Women are not ordained to the priesthood, but occupy leadership roles in some church organizations.Both men and women may serve as missionaries; the church maintains a large missionary program that proselytizes and conducts humanitarian services worldwide. Faithful members adhere to church laws of sexual purity, health, fasting, and Sabbath observance, and contribute ten percent of their income to the church in tithing. The church also teaches about sacred ordinances through which adherents make covenants with God, including baptism, confirmation, the sacrament, priesthood ordination, endowment, and celestial marriage.