Established in 1841 by Pierre DeSmet, S.J., in response to requests for Black Robes by four separate delegations sent by Flathead and Nez Perce tribes to St. Louis, Saint Mary's Mission became the place where DeSmet and his party erected Montana's first church on the bank of the Bitter Root River immediately west. They planted the first garden, harvested the first wheat and oats, practiced first irrigation, bred first livestock, taught first classes, and organized the first musical band. Saint Mary's was also the site of the first flour and lumber mills. Fr. Ravalli, for whom this county is named, served there during 1845-1850 and 1866 until his death in 1884. St. Mary's ceased to be an Indian mission in 1891, when the Flathead-Salish were forced to remove to a reservation, and the chapel served settlers until 1954, when a new church was built and the mission became a historic site.