The first Northern (4-8-4) type locomotives built for the Great Northern were delivered in 1929 from the Baldwin Locomotive Works (#2550-#2555). Designated Class S-1 the six engines were heavy, dual service oil-burners and remained in service until the 1950s. None has survived.

Between March and April 1930, the Great Northern took delivery of another fourteen Northerns from Baldwin (#2575-#2588). Designated Class S-2, they were lighter than the S-1 Class with higher drivers, specifically intended for fast passenger service. The locomotives were assigned to the railroad's Montana division working between Williston, ND, and Havre, MT, and the Spokane division for service between Spokane, WA, and Wenatchee, WA, hauling the Empire Builder and recently inaugurated Minneapolis, MN-Seattle, WA, Oriental Limited.

The S-2s were bumped from the Empire Builder and Oriental Limited in 1949 when the services were

dieselised, and relegated to secondary passenger and freight trains . During the 1950s, they were all repainted from their original Cascade Green to a more utilitarian black.