Holt Atherton's Small California Collections span the region's history from 1806 to the present. Their particular emphasis lies in the the first fifty years of statehood, where they are especially strong in materials pertaining to Biography, Business, Mining, Politics and Social History, notably, with regard to San Joaquin County, home of Holt Atherton Special Collections. Certain prominent California names are represented in the collections, including: Ignacio Martinez de la Vega, John Bidwell, James Marshall, David Broderick, John Swett, Jessie Benton Fremont, Collis P. Huntington, John Muir, Edwin Markham and Denis Kearney. However, the bulk of these folder-size collections represents the efforts of lesser-known farmers, merchants, scholars and laborers who helped make California the large and wealthy state it is today.

Collection is open for research.