The Dubuque County Historical Society (DCHS) has its roots in the Richard Herrmann Museum of Natural History, established in the 1870s. The DCHS was formed in 1950 as a private, non-profit organization with a focus on oral and archival history; and it opened its first museum, the Mathias Ham House, in 1964. Over the past 25 years the DCHS has successfully raised $54 million to organize 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 9 percent of American museums, was named an affiliate of the Smithsonian Institution in August 2002, and was accredited by the Association of Zoos & Aquariums in 2009.