The Research Library at the Humboldt County Historical Society includes the following resources:
  • Books on Humboldt history from Elliott's History of Humboldt County, published in 1881, to the recent (2010) publication of Place Names of Humboldt County. The books in our library are organized by areas of interest, including Native peoples, Indian-White interactions, maritime, logging and railroad activities, geographical locations within the county and our neighboring counties.

  • A complete collection of the Humboldt Historian from its inception in 1953 as a monthly newsletter to the most current issue.

  • A set of city directories, our earliest being a photocopy of the 1877 Eureka directory, with the series continuing through 2003. Although not inclusive, our collection is fairly complete and we continue to add to it.

  • General information files contain folders arranged by subject matter with materials such as newspaper clippings, pamphlets, reports and programs. Other items that are considered "ephemera" such as commercial billheads, tourist brochures and programs for specific events are housed in boxes in the Research Library hallway and are organized by subject matter.

  • Notebooks, cards and general information files created by the late Martha Roscoe, a local historian.
In the HCHS Research Library, J. P. Smith, retired professor of botany, Humboldt State University, researches early Eureka botanist Joseph Prince Tracy, who made significant contributions to the study of flora of the North Coast region.