The Dubuque County Historical Society has its roots in the Richard Herrmann Museum of Natural History, established in the 1870s. The Society was organized in 1950 as a private, non-profit organization with a focus on oral and archival history, and opened its first museum, the Mathias Ham House, in 1964. Over the past 25 years, the museum has successfully raised $54 million to establish and expand its Mississippi River Museum into the National Mississippi River Museum & Aquarium. The Museum & Aquarium is accredited by the American Association of Museums - a distinction held by only nine percent of American Museums - and was named an affiliate of the Smithsonian Institution in August 2002.