=Overview=
The church is established in
Nauvoo during the early part of this decade. The
Nauvoo Temple is begun and completed and later destroyed.
The most important event in this decade concerning mormonism is the martyrdom of Joseph Smith, Jr. After his death, the majority of the Saints leave Nauvoo behind and head west under the direction of
Brigham Young . The
Succession Crisis fractures Joseph Smith Restorationism into many different denominations, although most of the Saints stay with the original Church.
- January 19 - Revelation is received by Joseph Smith ordering the church to build a temple in Nauvoo. Also, the order of baptism for the dead is laid out. The church is also excused from building the temple in Jackson County due to the persecution at that time. (D&C 124)
- May 6 - A gunman shoots into Governor Boggs home, hitting him four times. The gunman is not found, but his revolver was left at the scene. Rumor and speculation points to Porter Rockwell , Joseph Smith's personal bodyguard, as the would-be assassin. Rockwell denies this, remarking that if it was him, Boggs would not have recovered.
- May 28 - An anonymous contributor to ''The Wasp'', a Mormon newspaper in Nauvoo, wrote that, "Boggs is undoubtedly killed according to report; but who did the noble deed remains to be found out."
- August 20 - Elder Orson Pratt is excommunicated for refusing to accept the doctrine of plural marriage.
- September 1 & 6 - Joseph Smith writes two letters to the church regarding baptism for the dead, clarifying the doctrine and practice. (D&C 127, 128)
- The Illinois legislature consider revoking Nauvoo's charter, but fail to act. Joseph Smith petitions the federal congress to make Nauvoo a territory. His petition is denied.
- July 12 - Joseph Smith receives revelation concerning eternal marriage, or "the new and everlasting covenant". (D&C 132)
- June 7 - The first and only issue of the '' Nauvoo Expositor '' is published by men angry with Joseph Smith and the Church. It is highly critical of Smith and his doctrines and practices.
- June 10 - After being declared a public nuisance by the Nauvoo City Council, the printing press of the ''Nauvoo Expositor'' is destroyed.
- June 12 - Charles A. Foster, a co-publisher of the ''Nauvoo Expositor'', reports that the destruction of the ''Expositor'' printing press two days earlier was carried out by several hundred people and the building the machine was housed in was damaged. The city marshall contradicts him, claiming that the destruction was carried out in an orderly fashion. The building stands for at least ten more years.
- June 18 - Amid threats of violence concerning the destruction of the ''Nauvoo Expositor'', Joseph Smith, Jr., as mayor, declares Martial Law in Nauvoo and activates the Nauvoo Legion , a private militia of about 5,000 men.
- June ?? - Joseph Smith, Jr. submits to arrest and agrees to trial in Carthage, Illinois , the county seat. Before he arrives, he prophesies, "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 toward God and toward all men. If they take my life I shall die an innocent man, and my blood shall cry from the ground for vengeance, and it shall be said of me 'He was murdered in cold blood!'" {Link without Title} He is held in Carthage Jail.
- October - The first general conference of the church under Brigham Young 's direction is held.
- The population of Nauvoo is estimated to have reached about 12,000 inhabitants, becoming the second-largest city in Illinois. Chicago had about 15,000 inhabitants at the same time.
- May 1 - The Nauvoo Temple is completed and dedicated, despite the majority having already left Nauvoo.
- Under the direction of Brigham Young , the largest numbers of saints begin migrating west to settle; they eventually arrive at the Salt Lake Valley .
- June 27 - Elder John E. Page is excommunicated from the LDS church for encouraging members to follow Strang.
- July - The Mormon Battalion is formed. Brigham Young prophesies that the recruits won't see battle and will perform a great service for their country. Many people join up despite the difficulties of the time. They send as much money to their families and the church as possible.
- January 14 - Brigham Young receives D&C 136 by way of revelation, which concerns the organization of the westward movement, standards of behavior for the saints, and an explanation on why God allowed Joseph Smith to be killed.
- January - The Mormon Battalion completes the longest march in U.S. Army history, arriving in California.
- February 2 - The Treaty Of Guadalupe Hidalgo is signed, which will grant the territory that the mormons are settling to the United States.
- March 10 - The U.S. Senate ratifies that Treaty Of Guadalupe Hidalgo , making the treaty official and thus officially making the area part of the United States.
- June 9 - The Miracle Of The Gulls occurs. It is attributed to saving the crops of the first settlers in Utah.
- The Nauvoo Temple is burnt down. The remnants are destroyed by a tornado.
- Mormon Battalion members who stay behind in California to raise money discover gold in Sutter's Mill . News of the find spreads, starting the 1849 California Gold Rush .
- December - Apostle Lyman Wight is excommunicated from the church for not following Brigham Young.
