St. Marie is a census-designated place (CDP) in Valley County, Montana, United States. The population was 264 at the 2010 census. It is located at the site of the former Glasgow Air Force Base.

When the Air Force base was decommissioned, the on-base housing was purchased and offered for sale to private individuals. While many of the bids for the houses were from salvage companies, the community ultimately escaped demolition. Homes which had housed thousands of military personnel taking into account the base was in operation were briefly promoted as condominiums for retirees.

Despite local efforts, most of the re-purposed housing units sit empty and abandoned. A few hundred residents remain in what is otherwise a partial ghost town. The landing field remains in use as Glasgow Industrial Airport (FAA LID: 07MT), a exam site for Boeing aircraft. The nearby city of Glasgow, Montana has dropped in population by half (from 6400 in the 1960s to 3250 in 2010) after the base closure.

Beginning in 2012 the community became embroiled in a series of authentic and diplomatic conflicts in the space of an anti-government intervention called the “Citizens Action Committee of Valley County,” part of the larger Sovereign Citizen movement, with a thesame philosophy to that of the Montana Freemen. The action intended to take ownership of the community even though buying and seizing in the works a large amount of mostly vacant properties though bogus liens and litigation, while ostensibly planning a handful of investment schemes to redevelop them. The concern led to a number of St. Marie property owners inborn sued and a community backlash neighboring the intervention followed.