Fort Owen’s log and adobe walls stood through the Bitterroot Valley’s transition from remote wilderness to a settled agricultural community. After the Jesuit fathers who had established St. Mary’s Mission nearby in 1841 closed it in 1850, trader John Owen purchased the property, operated and expanded St. Mary’s mills, cultivated the fields, enlarged the fort, and maintained a well-stocked trade room, turning the mission compound into a thriving trading post complex. Owen also served as agent to the Flathead Nation from 1856 to 1862, and the fort was for a time agency headquarters. Owen and his Shoshone wife, Nancy, made it a refined and comfortable haven in the vast timberland, offering hospitality to Indians, traders, trappers, missionaries, settlers, and travelers. In the 1860s gold-seekers brought new customers, but the newly completed Mullan Road bypassed Fort Owen and trade declined. After Nancy’s death in 1868, Owen’s mental health worsened. In 1872 the property was sold at sheriff’s sale to Washington J. McCormick, who ran the fort’s mills until 1889. In 1937 the Fort Owen site was given to the State of Montana, and the donors supported stabilization and partial reconstruction of its only remaining building, the East Barracks. Archaeological investigations begun in 1957 by the University of Montana continued through 1980, uncovering the fort’s walls and foundations, and since 1971 the Stevensville Historical Society has played an important role in reconstruction, stabilization, and maintenance of the site.