This is the Neutral point of view on the subject Mormonism. for the Mormon point of view visit Mormonism (Mormon point of View)
Mormonism refers to the practices, culture, and particularly the religion of followers of the Latter Day Saint Movement. The movement first began in 1820 with the first vision of Joseph Smith Jr. As directed by God, he restored the church that Christ established during his mortal ministry on Earth, with the first meeting of the church, officially named as The Church of Jesus Christ of Latter-day Saints held on 06 April 1830 in Palmyra (town), New York. As there were many dissenters and persecutors that plagued the the newly established Church, the Saints were forced to move several times, eventually starting their own city, Nauvoo, in the swamplands near the Mississippi River. In 1844, due to severe persecution and injustice, Smith, a self-proclaimed prophet, was martyred in Carthage, Illinois at Liberty Jail.
Though the movement had a large share of dissenters previous to this time, this incident led to the largest fracture thus far. The resulting groups chose to follow different leaders, most following and sustaining Brigham Young as the second president of the Church, and made a migration to the west eventually setting the area now known as Utah, while others chose to stay in Nauvoo. The most popular alternative to Young at this point was a man named James J. Strang, baptized four months previous, he claimed he had been appointed by Smith as the rightful Successor of the Church. Though ultimately rejected by the body of the church and excommunicated , Strang led a following for several years until he was assassinated by a disaffected saint on Beaver Island. Others believed that Joseph Smith III, Joseph Smith's son to be the rightful successor. Joseph Smith III responded that he would only assume the church presidency if he were inspired by God to do so. In 1860, 16 years after his fathers death, Smith said that he had received inspiration that he was to preside over Gods church. He was sustained as President of the Reorganized Church of Jesus Christ of Latter Day Saints.
The result today is several religions that have a root in the teachings of Joseph Smith, but with variance. Of these groups The Church of Jesus Christ of Latter-day Saints, the followers of Brigham Young, is the largest having on record around 13,000,000 followers. While the Community of Christ, the followers of Joseph Smith III, (formerly The Reorganized Church of Jesus Christ of Latter-day Saints)is the second largest with around 250,000 followers. The Fundamentalist Church of Jesus Christ of Latter Day Saints has the third largest following with around 30,000 members.