| Centuries: | 18th century - 19th century - 20th century |
| Decades: | 1810s 1820s 1830s - 1840s - 1850s 1860s 1870s |
| Years: | 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 |
January[]
February[]
March[]
- March 5 - The provisional State of Deseret established and appeals made to the US Government to allow self-rule in the territory.
April[]
May[]
June[]
July[]
August[]
September[]
October[]
- October - Brigham Young instructed three of his Twelve Apostles to travel to continental Europe to organize proselyting missions in Scandinavia, France, and Italy.
November[]
December[]
- December 9 - The first Sunday School established in Salt Lake City.
Unknown Dates[]
Births[]
- February 5 - Charles Wilson Nibley, born to James Nibley and Jane Wilson. He later served as Presiding Bishop of the Church and as second councilor to President Heber J Grant.