Oliver Cromwell Applegate (1845-1938), the son of Lindsay and Elizabeth Applegate (Applegate Trail pioneers), spent his career working with Oregon Indians. He was a subagent with the Indian Service at Yainax, and during the Modoc War he served as an interpreter and a scout. In 1873, he became a U.S. Commissioner, and in 1898 was appointed Klamath Indian Agent. After his resignation in 1905 he continued to work with the federal government on Indian issues such as the Grande Ronde tribal status challenge. The Oliver Cromwell Applegate papers consist mainly of Applegate family correspondence, with some miscellaneous bills, newspaper clippings, pension papers, documents, journals and the 1868 diary of Frank Applegate.
This collection documents the Calbreath and Smith families, both pioneer families in Oregon. The collection contains incoming and outgoing correspondence, diaries, account books, day books, and manuscripts of poetry and prose by Irene Smith Calbreath.