Collection contains various items related to Pratt's missionary service and letters with his wives and other family. Includes a handwritten diary of Pratt and his wife, Phoebe Sopher Pratt, kept while the Pratts were on a mission for The Church of Jesus Christ of Latter-day Saints in South America from 1851 to 1852. Also included are three handwritten letters and eight fragments of manuscripts by Parley P. Pratt. All items date from 1851 to 1855.

A fragment of a holograph manuscript, likely a draft of a tract Parley P. Pratt intended to publish while on his mission. Focuses on doctrines related to Jesus Christ and his Church, and arguments against modern-day churches and creeds. 7 pages. Date of production not identified, but likely 1851.