Mormons consider Joseph Smith, Jr. (1805–1844), the founder of the Church of Jesus Christ of Latter-day Saints (Mormon Church), to be a true prophet. The Prophet Joseph, who was ultimately killed by his religious and political foes, is remembered as a martyr for the cause.

On June 25, 1844, Governor Thomas Ford of Illinois told the state militia that Joseph and his brother Hyrum were "dangerous men" (History of the Church, 5:563) and guilty of treason. The two brothers went to Carthage, Illinois , to deliver themselves up to the "pretended requirements of the law" (Doctrine and Covenants 135:1), according to the demands of the governor. Joseph Smith said of the event, "I am going like a lamb to the slaughter; but I am calm as a summer’s morning; I have a conscience void of offense towards God, and towards all men. I shall die innocent, and it shall be said of me—He was murdered in cold blood" (Doctrine and Covenants 135:4).

After delivering themselves up, Joseph and Hyrum were confined in Carthage Jail. The men were accompanied by John Taylor and Willard Richards, members of the Church administrative body known as the Quorum of the Twelve. The four men remained in the jail for two days, during which time the jailers treated them well and friends visited them. On June 27, 1844 a mob, made up of members of the town militia who were in charge of protecting Joseph, overran the jail. The mob, later described by John Taylor as men who were "armed" and "painted black" (Doctrine and Covenants 135:1) entered the room in which the men were being held. The room was on the second floor of the jail, at the top of the stairs. The mob forced the door open and poked their gun barrels into the room. They began shooting, despite efforts by Willard Richards to deflect the gun barrels with his walking stick. Hyrum Smith was shot multiple times and died, falling to the floor. John Taylor was also shot in several places. He was not killed but sought refuge by rolling under the bed. Joseph Smith ran toward the window where he was shot in the back from inside the jail and shot in the chest from outside the jail. He either fell or leaped out of the window, landing on the ground outside the jail, where he was again shot by members of the mob. The Prophet Joseph Smith died at that time. (See History of the Church, 6:602-618, also Doctrine and Covenants Student Manual, 348).

John Taylor and Willard Richards were both present at the martyrdom and survived. John Taylor, who later became the third President and Prophet of the Church, wrote: "Hyrum was shot first and fell calmly, exclaiming: I am a dead man! Joseph leaped from the window, and was shot dead in the attempt, exclaiming: O Lord my God! They were both shot after they were dead, in a brutal manner " (Doctrine and Covenants 135:1).

To this day, Joseph Smith is remembered by Mormons as the first prophet of the Restoration, accomplishing tasks that established the Lord's true Church again to the earth. John Taylor makes this point clear, in his record:

"Joseph Smith, the Prophet and Seer of the Lord, has done more, save Jesus only, for the salvation of men in this world, than any other man that ever lived in it. In the short space of twenty years, he has brought forth the Book of Mormon, which he translated by the gift and power of God, and has been the means of publishing it on two continents; has sent the fullness of the everlasting gospel, which it contained, to the four quarters of the earth; has brought forth the revelations and commandments which compose this book of Doctrine and Covenants, and many other wise documents and instructions for the benefit of the children of men; gathered many thousands of the Latter-day Saints, founded a great city, and left a fame and name that cannot be slain. He lived great, and he died great in the eyes of God and his people; and like most of the Lord’s anointed in ancient times, has sealed his mission and his works with his own blood; and so has his brother Hyrum" (Doctrine and Covenants 135:3).

Mormons believe that Joseph Smith is a "testator," meaning he "provided to mankind a witness of God’s covenants." When Joseph Smith died, his death "place[d] a seal of truth on the testament" (Doctrine and Covenants Student Manual, 350).

Joseph Smith, Jr. gave his life to the cause of building what is known by some as the Mormon Church, Mormons believe Joseph Smith, through divine guidance and instruction, introduced the restored Gospel of Jesus Christ back to the earth. After having restored precious truths that had long been lost, through the power of the Lord, the Prophet Joseph sacrificed his life. Mormons today "look to the Prophet with reverence because of what he did for their understanding of Jesus Christ and His mission" (Doctrine and Covenants Student Manual, 349). In this way Mormons are ever grateful to Joseph Smith's righteousness and obedience to the divine mission he had in life. 

约瑟夫·史密斯是摩门教的创始人，他是一个农场主。1830年，他受莫罗尼的影响创建了摩门教，教徒的信仰就是一夫多妻制。该教一创立就吸引了大量的追随者，以至于发展得越来越壮大，从俄亥俄州到密苏里州再到伊利诺斯州，几乎到处都有摩门教教徒，这个教派的迅速发展和取得的极大成功在历史上是罕见的，以至于反对摩门教的人认为摩门教已经在政治、经济和宗教方面对他们构成了极大的威胁，所以摩门教在发展的同时也受到了残酷的打击，史密斯于1844年被人谋杀。一夫多妻制在美国是被禁止的，它也是一种重婚罪，但这里的人并不躲躲闪闪的，他们“正大光明”地娶许多妻子，生许多孩子。一个叫格雷顿·哈德森的人公开与他的五个妻子和21个孩子在盐湖城南的郊区生活在一起，他说：“我一点也不惧怕法律，我甚至都不去管它。”这种习惯是从很早的上个世纪传下来的，那时，在犹他州和美国西部的大部分地方十分盛行一夫多妻，是宗教和“山高皇帝远”的环境培养的结果。