When the London Midland Scottish Railway came up with its initial standard designs in 1947, it was considered that there was no call for a mixed traffic Class 4, 4-6-0 locomotive. The duties for which the 4-6-0 design were suited to were amply covered by existing traction types and it wasn’t until Nationalisation, in 1948, that the Western Region of British Rail felt that this type of locomotive was required for use on its secondary route services.