Contains diaries, personal and family memorabilia, pamphlet library, writings, and correspondence. Dated 1839-1978 (bulk 1877-1965).

Contains three sprial-bound booklets of newsletters from Lyon to his brothers. Dated 1977-1994.

Contains newsletters to and from members of the T. Edgar Lyon family, mostly the children. Dated 1979-1995.

Collection contains research files, correspondence, diaries, memorabilia, and other materials related to the Lyon family. Includes professional materials associated with various family members, as well as historical information on the Church of Jesus Christ of Latter-day Saints. Materials date from approximately 1836 to 2007, with most from between 1899 and 1995.

Additional T. Edgar and Hermana Forsberg Lyon family records added in 2023.

Collection includes photographs and negatives collected by John Lyon of himself and other members of his family. The negatives are all copy negatives; some of the photographs are copy prints and some are original. Materials dated approximately 1850-1906.