| 1801 | June 1 | Born in Whitingham, Vermont, to John Young and Abigail Howe. |
| 1804 | | Family moves to Sherburne, New York. |
| 1806 | June 7 | Miriam Works born to Asa Works and Abigail Marks in Aurelius, New York. |
| 1808 | June 8 | Mary Ann Angell born to James Angell and Phebe Ann Morton in Providence, Rhode Island. |
| 1815 | June 11 | Brigham Young’s mother, Abigail Howe Young, dies of tuberculosis. |
| 1817 | | Begins trade as carpenter, painter, glazier in Auburn, New York. |
| 1823 | | Joins Reformed Methodist Church. |
| 1823 | May 26 | Purchases one-acre lot in Port Byron, New York, for $60. |
| 1824 | October 8 | Marries Miriam Works in Aurelius, New York. They lived in the Aurelius, Haydenville, and Port Byron area for nearly five years. |
| 1825 | September 26 | Elizabeth Young born to Brigham Young and Miriam Works in Port Byron, New York. |
| 1829 | | Spring Family moves to Mendon, New York. |
| 1830 | | Spring First introduction to the Book of Mormon. |
| 1830 | June 1 | Vilate Young born to Brigham Young and Miriam Works in Mendon, New York. |
| 1831 | Fall | First hears Mormon elders preach in Mendon, New York. |
| 1832 | April 9-14 | Baptized by Eleazer Miller at Mendon, New York. Ordained an elder. Miriam Works Young baptized about three weeks later. |
| | September 8 | Wife, Miriam Works Young, dies of consumption and tuberculosis. |
| | September–October | Travels to Kirtland, Ohio; meets Joseph Smith. |
| 1833 | January 2 | Leaves on proselytizing mission to Canada with his brother Joseph Young. |
| | ca. March 1 | Returns to Mendon, New York. |
| | April–August | Departs on another mission to Canada. |
| | May 20 | Baptizes Warren Parish and members of the David Patten family. |
| | September | Moves family from Mendon, New York, to Kirtland, Ohio. |
| | September 4 | Performs his first civil marriage for Jonathan Hampton and Julia Foster, Lyons, New York. |
| | November 12 | Witnesses the Leonid meteor shower. |
| 1834 | February 18 | Marries Mary Ann Angell in Kirtland, Ohio. |
| | May–July | Travels to Missouri and back with Camp of Israel (Zion’s Camp). |
| | Summer–Fall | Labors on construction of temple and printing office in Kirtland, Ohio |
| | October 14 | Joseph Angell Young born to Brigham Young and Mary Ann Angell in Kirtland, Ohio. |
| 1835 | February 14 | Appointed to Quorum of Twelve Apostles. |
| | May 4–September 26 | Mission to eastern United States with the Twelve. |
| | May 25–May 31 | With John P. Greene and Amos Orton preached to Native Americans, including Seneca and Iroquois, in Cattaraugus County, New York. |
| 1835 | June 16 | Testifies on behalf of Joseph Smith at Court of Common Pleas: Lake v. Smith. |
| | Fall | Attends Hebrew school in Kirtland. |
| 1836 | March 27 | Attends Kirtland temple dedication. |
| | Summer | Proselytizing mission to the eastern United States. |
| | December 18 | Twins Mary Ann Young and Brigham Young Jr. born to Brigham Young and Mary Ann Angell in Kirtland, Ohio. |
| 1837 | March–June | Business mission to eastern states with Willard Richards. |
| | July–August | Mission to New York and Massachusetts. |
| | December 22 | Forced to leave Kirtland, Ohio, for safety. |
| 1838 | March 14 | Arrives at Far West, Missouri, with Joseph Smith. |
| | April 6 | Church conference sustains Brigham Young in the Missouri presidency pro tempore. |
| | July 8 | Joseph Smith revelations provide direction for the Twelve to preach abroad. |
| | Fall | Organizes the Latter-day Saint evacuation of Missouri as a result of the Mormon War and the governor’s extermination order. |
| | December 17 | Baptizes Asa Works. |
| 1839 | February | Helps lead Saints and moves family to Quincy, Illinois. |
| | March 17 | Takes lead in meeting of Quincy Saints. |
| | April | Travels to Far West, Missouri, with the Twelve. |
| | May 23 | Moves family to Montrose, Iowa Territory, with the Woodruff family. |
| 1839 | June–July | Farewell blessings, instructions, and recommendations given to members of the Twelve Apostles before leaving for England. |
| | July | Malaria hits the swampy Mississippi lowlands in Illinois and Iowa Territory. Brigham Young and family affected along with many other church members. |
| | September 4 | Alice Young born to Brigham Young and Mary Ann Angell in Montrose, Iowa Territory. |
| | September 14 | Very ill, departs for mission to England lying in a wagon bed. |
| | October 12 | Father, John Young, dies in Quincy, Illinois. |
| | November 17 | Preaches in Kirtland, Ohio, and anoints John Taylor in the Kirtland temple. |
| 1840 | January 31 | Arrives in New York City. Preaches in the Columbian Hall two days later. |
| | March 9 | Departs New York City for England with Heber C. Kimball, Parley P. Pratt, Orson Pratt, and George A. Smith on the ship Patrick Henry. |
| | April 6 | Arrives in Liverpool, England. |
| | April 14 | First council of the Quorum of the Twelve held abroad; Brigham Young sustained as president; Willard Richards ordained an apostle. |
| | April 15 | First general conference held with English Saints, Liverpool, England. |
| | May 25 | Visits printers in Manchester, England, for first time about printing British editions of the Book of Mormon, the Doctrine and Covenants, and a Latter-day Saint hymnal. |
| | May–December | Visits and preaches in settlements and cities throughout England. |
| | December 29 | Makes down payment to printers to print British editions of the Book of Mormon, the Doctrine and Covenants, and a Latter-day Saint hymnal. |
| 1841 | March 25–27 | Serves as a witness in the case of “The Queen v. Joseph Holloway,” Liverpool, England. |
| | April 6 | Conference with and farewell to the Saints in Manchester, England. Nearly 6,000 members in England at this time. |
| | April 21 | Departs England to return home. |
| | July 1 | Arrives in Nauvoo, Illinois. |
| | July 9 | Joseph Smith revelation to Brigham Young encouraging him to care for his family. |
| | August 16 | Special church conference held in Nauvoo, Illinois, where Joseph Smith gave the “business of the church to the Twelve.” |
| | September 4 | Elected to Nauvoo City Council. |
| 1842 | June 14 | Marries Lucy Ann Decker, first plural wife. |
| | August 20 | Luna Caroline Young born to Brigham Young and Mary Ann Angell in Nauvoo, Illinois. |
| | November 26 | Falls ill of apoplexy and fever. Doesn’t leave house until 18 January 1843. |
| 1843 | May 26 | Received instruction on priesthood and the new and everlasting covenant from Joseph Smith. |
| | May 29 | Sealed for eternity to Mary Ann Angell Young. |
| | July 1 | Deposed in Nauvoo city court regarding Joseph Smith in Missouri. |
| | July–October | Mission to eastern United States to collect funds for building the Nauvoo House and temple. |
| | August 27 | Daughter Mary Ann Young dies at six years old in Nauvoo, Illinois. |
| | November 2 | Marries Augusta Adams and Harriet Cook as plural wives. |
| | November 8 | Among first signers of “Scroll Petition” to Congress for reparations resulting from the Saints’ Missouri experience. |
| 1844 | January 29 | The Twelve and others meet in Nauvoo to nominate Joseph Smith as a candidate for president of the United States. |
| | February 21 | The Twelve meet to select first men for western expedition. |
| | March 11 | Attends organizing meeting of Council of Fifty. |
| | April | At the conference of the church, 244 missionaries volunteer to stump for Joseph Smith’s presidential campaign and to teach the gospel of Jesus Christ. |
| | May 8 | Marries Clarissa Decker as plural wife. |
| | May 21 | Begins mission to eastern United States to solicit support for Joseph Smith’s presidential candidacy. |
| | June 1 | Holds conference in Pittsburgh, Pennsylvania, with John E. Page. |
| | June 27 | Joseph and Hyrum Smith killed at Carthage, Illinois. |
| | ca. July 16–18 | In Peterborough, New Hampshire, when hears of Joseph Smith’s death. In Boston, Massachusetts, gives counsel to the Saints regarding the murder of Joseph Smith. |
| | August 6 | Arrives in Nauvoo from mission to the eastern United States. |
| | August 7 | Meeting of church leaders in Seventies Hall, determining that the kingdom rests with the Twelve. |
| | August 8 | Asserts right of the Twelve to lead the church in opposition to claims of Sidney Rigdon. Young and the Twelve Apostles sustained by vote of conference. |
| | August 31 | Elected lieutenant general of Nauvoo Legion. |
| | September | Marries Emily Dow Partridge as plural wife. |
| | September 8 | Public six-hour trial of Sidney Rigdon and others; they are cut off from the church. |
| | September 10 | Marries Clarissa Ross as plural wife. |
| | September 19 | Marries Louisa Beaman as plural wife. |
| | October 1 | John Willard Young born to Brigham Young and Mary Ann Angell in Nauvoo, Illinois. |
| | October 3 | Marries Eliza Roxcy Snow and Elizabeth Fairchild as plural wives. |
| | October 6–8 | General conference held in Nauvoo, first one without Joseph and Hyrum Smith; Brigham Young presides. |
| | October 8 | Marries Clarissa Blake as plural wife. |
| | October 9 | Marries Rebecca Holman as plural wife. |
| | October 10 | Marries Diana Chase as plural wife. |
| | October 31 | Marries Susannah Snively as plural wife. |
| | November 7 | Marries Olive Gray Frost as plural wife. |
| | November 12 | Issues circular urging immigrants to buy Nauvoo land from the church. |
| | December 19 | Almon Babbitt reports to Young that the Illinois legislature would repeal the Nauvoo charter. |
| | December 31 | Gives sermon on the Godhead and exaltation in Nauvoo, Illinois. |
| 1845 | | Directs preparations for the Saints to leave Nauvoo. |
| | January 1 | Illinois Senate bill passed for “unconditional repeal” of Nauvoo charter. |
| | January 14 | General epistle to the church on gathering and on finishing the temple in Nauvoo. |
| | January 15 | Marries Mary Ann Clark as plural wife. |
| | January 16 | Marries Margaret Pierce and Mary Pierce as plural wives. |
| | January 22 | Issues circular urging help in building Nauvoo temple. |
| | February 4 | Council of Fifty meets for first time since the death of Joseph Smith; council is reorganized with Young as standing chairman. |
| | February 15 | Brigham Young’s father-in-law, Asa Works, dies. |
| | March 2 | Brigham Young visits “Mother” Lucy Mack Smith. |
| | April 6 | Issues proclamation to world leaders declaring restoration of kingdom of God on the earth. |
| | April 6–7 | 15th annual general conference; the largest crowds thus far sustained church officers. |
| | April 30 | Marries Emmeline Free as plural wife. |
| | May 10 | Writes long letter to US president James K. Polk recounting the church’s past and asks for help in their current situation in Illinois. |
| | May 22 | Marries Mary Elizabeth Rollins as plural wife. |
| | May 24 | Capstone laying ceremony 6:00 a.m. |
| | September 16 | Issues proclamation announcing intent of Latter-day Saints to leave Nauvoo. |
| | September 24 | Goes with about fifty others to Carthage to surrender on treason; visit Carthage Jail. |
| | October 5 | First meeting in Nauvoo temple; Brigham Young gave an opening prayer as a “form of dedication prayer.” |
| | October 6–8 | General conference held in Nauvoo temple; the congregants vote to move en masse to the West. |
| | December 10 | Temple ordinances begin in Nauvoo temple. |
| | December 12 | Fully engaged in overseeing and officiating in temple as first priority. |
| 1846 | January 7 | Dedicates the altar in the Nauvoo temple. |
| | January 14 | Marries Margaret Alley as plural wife. |
| | January 15 | Marries Olive Andrews and Emily Haws as plural wives. |
| | January 21 | Marries Martha Bowker and Ellen Rockwood as plural wives. |
| | January 28 | Marries Jemima Angel, Abigail Marks, Phebe Morton, and Cynthia Porter as plural wives. |
| | January 31 | Marries Mary Eliza Nelson and Rhoda Richards as plural wives. |
| | February 2 | Marries Zina Huntington as plural wife. |
| | February 3 | Marries Amy Cecilia Cooper, Mary Ellen de la Montague, Julia Foster, Abigail Harback, and Mary Ann Turley as plural wives. |
| | February 15 | Leaves Nauvoo to lead Latter-day Saint exodus west. |
| | February 28 | Petitions governor of Iowa for aid and protection during exodus from Nauvoo. |
| | June 14 | Arrives at Council Bluffs, Iowa, on east bank of Missouri River. |
| | July 1 | Advocates raising of Mormon Battalion. |
| | Fall | Establishes Winter Quarters on west bank of Missouri River. |