The Gallatin Historical Society, founded in 1977, moved into two rooms in the County Jail building in 1979. Built in 1911, the jail was already considered a historic structure. When prisoners were moved to new quarters in January 1982, the County Commissioners granted the Society use of the entire building for a museum. The Pioneer Museum was created and, in 2014, the name changed to Gallatin History Museum to better reflect the collection and the mission of the organization which is to preserve, promote and foster the history of Gallatin County and southwest Montana.
The Gallatin History Museum is a 501 (3)(c) nonprofit and is operated by the Gallatin Historical Society. It is not a County agency and does not receive any tax dollars, but instead relies strictly on memberships, donations, and memorials to operate. In addition to jail cells and a hanging gallows, the museum maintains displays illustrating the unique histories of a variety of people who have called southwest Montana home.