In the early 50"s the SNCB sought an alternative to steam motive power for branch lines, that could be not be electrified economically, and as an interim solution for main lines until the catenary was extended. At this time the only interesting sources for wide-spread use of efficient diesel locomotives were in the United States. Consequently, the introduction of diesel motive power on the SNCB required collaboration between the American companies and the Belgian railroad equipment manufacturers.
At the end of 1953 the SNCB placed an order for 55 four-axle type 201 locomotives that were to be assembled in the John-Cockerill plant in Seraing. They were intended for the routes in the northern plain of Sambre and Maas with their easy grades and were fitted with a Baldwin motor. The first regular production locomotive was delivered in December of 1954. The last of these long-lived locomotives was still pulling the work trains used to build the high-speed lines in France and Belgium in June 2002.
When delivered from the Cockerill plant all 201 class locomotives were designed with a splendid two-tone paint scheme version, the so-called "star". Two colors were used for the body: The lower half was light green; the upper half was dark green. Broad yellow side stripes ran to both ends and crossed under a majestic symmetrical star. This paint scheme was simplified in the mid Sixties, when certain work was performed on the chassis for safety and maintenance reasons (steps and additional hand rails were installed).