The History Museum at the Castle is currently under the management of the Outagamie County Historical Society. It boasts of one of the best collections of Fox Valley artefacts, with its wide selection of exhibits and collections. Photographs, narrative accounts, and objects collected by the museum date as early as the 1840?s. Exhibits in the museum feature both local and natural events to provide visitors with a broader understanding of Fox Valley?s history. The museum also regularly holds magic workshops and celebrates Houdini holiday events.

The present location of the museum used to be a Masonic temple and has since been listed in the National Register of Historic Places.

In the past, the History Museum had been known as the Outagamie Museum.