John Commingers Ainsworth (1822-1893) was the major founder of the Oregon Steam Navigation (OSN) Company, the most powerful transportation monopoly in the Pacific Northwest. Ainsworth was also involved in a number of other ventures, including the Northern Pacific Railroad (NPRR) and various gold, silver and coal mining operations. The John Commingers Ainsworth Papers contain Ainsworth's diaries, autobiography, personal correspondence, photographs, and the business records of the Oregon Central Railroad, Oregon Steam Navigation Company, Northern Pacific Railroad Company, and various mining, building and shipping enterprises.
Robert Aubrey Miller (1854-1941) graduated from Willamette University in Salem, Oregon in 1878, and began a law practice in Jacksonville, Oregon, served in the Oregon House of Representatives, and was as an aide to Governor Sylvester Pennoyer. The collection contains correspondence, letterpress volumes, a diary, proceedings of the Jacksonville District Pomona Grange (1876-1879), a Willamette University memorandum book, scrapbooks of clippings, speeches, Southern Oregon District Fair material, books of poems, excerpts from The Hesperian, a literary magazine edited by Miller, and photographs.