The Josiah Osborn Daybook contains a daybook kept by Josiah Osborne from 1833 to 1876.

The Whitman Mission National Historical Site Collection, which dates from 1947 to 1987, contains materials related to the Whitman Mission Historical Site, a memorial for Marcus and Narcissa Whitman and their impact on the Oregon Trail and the Native American population. The collection contains informational booklets, newspaper clippings, correspondence, and an academic paper entitled "Whitman Mission Overview.”