The Church of the Firstborn of the Fulness of Times is a Church of Jesus Christ of Latter-day Saints fundamentalist sect headquartered in northern Mexico that was founded in 1955 by Joel LeBaron and members of his family. This letter (1963) is a photocopy of a circular letter signed by Verlan M. LeBaron proposing peace with the faction of the church under the leadership of Ervil M. LeBaron which it accuses of being responsible for murder and arson.

The Far West record (1833-1844) is a microfilm reel containing information on the Far West Stake of the Church of Jesus Christ of Latter-day Saints.

Scott Harry Faulring (1956-2018) was a Brigham Young University professor and researchers into the history of the Church of Jesus Christ of Latter-Day Daints. This collection contains photographs, slides, and negatives documenting Faulring's career as a researcher and in the United States Airforce, as well as images of Faulring's family and travels.

The R. Kent Fielding papers (1840-1998) consist of Fielding's writings and the research materials he gathered for them. The collection reflects his interest in the history of the LDS Church, the Mountain Meadows Massacre, and his transition from being a member of the LDS Church to being a secular humanist.

The Stanley S. Ivins papers (1850-1968) consist of correspondence, a diary, articles, and eleven microfim reels which contain research notebooks and transcripts of Salt Lake City newspapers.

The journal history of the Church of Jesus Christ of Latter-day Saints (1830-1972) contains diaries, letters, newspapers, and sermons on 304 reels of microfilm. The Church Historian's Office compiled a 1200-volume chronological scrapbook using diaries, letters, newspapers, sermons, and other materials.

The Heber Chase Kimball papers [microform] (1837-1914) contain diaries, histories, correspondence, and an inventory of the effects of Heber C. Kimball. Kimball was an early Mormon apostle and good friend of Brigham Young.

The Stanley Buchholz Kimball papers (1844-2003) contain documents pertaining to Kimball's research on the LDS Church and the Kimball family, as well as his interest in Eastern European history.

Stanley Buchholz Kimball (1926 –2003) was a historian of Central European History and the history of The Church of Jesus Christ of Latter-Day Saints. The Stanley Buchholz Kimball photograph collection contains slides and negatives documenting Kimball's life and his research.

The Kirtland Council minute book (1832-1837) is a copy of a microfilmed typescript consisting of meeting minutes of the Kirtland high council.

The history of the church is microfilmed history of the LDS Church written by scribes and taken from the diaries of Joseph Smith Jr.

The H. Michael Marquardt papers (1800-2017) contains correspondence, clippings, diary copies, scholarly articles, miscellaneous research materials on topics in LDS history and theology. Marquardt is a historian and author.

The Eldon T. McEntire papers (1926-1991) contain correspondence, articles, tests, financial materials, notebooks, fliers, pamphlets, booklets, teaching materials for the Church of Jesus Christ of Latter-day Saints (LDS Church) and the Young Men and Young Women Mutual Improvement Association (YMMIA and YWMIA), and news clippings.

The A. Milton Musser papers (1952-1948) consist of typescripts of diaries (1852 and 1869 February-April), a handwritten index of Musser diaries (1852-1857), and a biography detailing associations with early LDS Church leaders as well as everyday activities. Collection includes a handwritten letter (dated 1948) about gold coins minted by the LDS in Salt Lake City. Musser was a traveling bishop for the LDS Church from 1858 to 1876.

The Ellen Gustava Stark Pack papers (1896-1952) consist of scrapbooks of newspaper clippings with information about the LDS Church and others filled with children's stories and games and places around the world.

The George Reynolds papers (1845-1906) consist of correspondence, writings, notes, family materials, diary photocopies, and other materials regarding the life of Reynolds and his family.

The George Reynolds photograph collection contains photographs of early notable members of the Church of Jesus Christ of Latter-day Saints, such as Joseph F. Smith, Prisoners of Conscience, etc. Also included in the collection is a portrait of George Reynolds.

The Wilford Woodruff papers (1833-1898) contain a handwritten document by Woodruff regarding the successions of the Mormon Church Presidency, concerning Orson Hyde and Orson Pratt and their placement in line of succession of the LDS Church. Also included are copies of his journal as well as a revelation from 1877. Wilford Woodruff was the fourth president of the Church of Jesus Christ of Latter-day Saints (LDS Church).