Towards the end of the 1930s, the Reichsbahn saw a need for a new passenger locomotive, which led to the development of the class 23 with the wheel arrangement 2-6-2. It was primarily intended to replace the Prussian P 8. Since the war that had just begun saw only a need for freight locomotives and passenger traffic was severely neglected, only two examples were built. After the war, however, these served as a model for a new variant in both parts of Germany, of which just over 100 were to be built.

After experience had already been gained at the beginning of the century in Prussia with the classes P 8 and G 10 of producing a passenger and freight locomotive with the same boiler, this principle was also applied here. Around the same time, the class 50 freight locomotive was built with a 2-10-0 wheel arrangement. Thus, the same boiler was used for both. In the development of the class 23, as with the 50, some new developments were dispensed with, which would have increased the possible boiler load by heating surface. As a result, however, the number of identical parts with earlier standard locomotives remained higher and production could also be carried out more cheaply. An improvement compared to older locomotives was a front wall on the tender. This fulfilled the same function as a closed cab and protected the crew when reversing.

Both examples came to the Reichsbahn of the GDR after the Second World War. In 1961, road number 23 001 received a modern, welded boiler with a combustion chamber, as was used on the Rekoloks. The second one was not rebuilt because its wheels and frame were damaged and was therefore retired in 1967. The remaining locomotive was renumbered 35 2001 in 1970 to distinguish it from the newly built post-war locos.

As already mentioned, further developments of the original 23 were made on both sides of the inner-German border after the war. The class 23¹⁰ of the DR kept almost completely to the dimensions of the prototype, but benefited from modern technical achievements and contemporary manufacturing methods. Between 1955 and 1959, 113 were made at the LKM Babelsberg. In contrast, the class 23 of the DB was based on BMAG's unimplemented plans for the alternative design of the 23. 105 of this variant were built between 1950 and 1959.