These Spanish Borderlands-related collections were processed with a grant from the National Historic Publications and Records Commission, and include research materials on the history of the Southwestern United States. The finding aids are accessible through the Online Archive of California (http://www.oac.cdlib.org/).

The Bolton Papers, originally processed in 1961, were brought up to current standards by improving the arrangement and description of his correspondence, writings, teaching materials, and other professional activities. His research materials, which are regularly used by scholars, remain in their original order. The total size of this collection is 211 linear feet.

A highlight of the Hammond Papers is his correspondence, which documents Hammond's wide network of historians in the Southwest, especially during the 1930s-1970s. Hammond was director of the Bancroft Library from 1946-1965 and is largely responsible for beginning the development of the library into its present-day form. This collection is 64 linear feet.

The Nasatir collection, at 15 linear feet, contains copies of documents from Spanish and American archives that he used to research the Spanish presence in the Missouri River Valley. These documents were used for his books Before Lewis and Clark (1952), and The Imperial Osages (1983), only two of his many writings from a career that spanned six decades. The bulk of his document collection was lost in a residential fire in 1985.