After the “Deutsche Reichsbahn” company consolidated dozens of railway companies in the different German states during the 1920s, a great step toward further unification was begun with the design of standard locomotives or “Einheitslocomotiven” which would be used on all routes.

The famous BR 01 Pacific was the first to emerge and this mighty express locomotive successfully replaced former designs from Prussia, Saxon, Bavaria and Baden.The BR 01 fulfilled all of her designer’s expectations- she was beautiful and her performance was as good as her looks. But hopes for the renovation of the German track system, which was in poor shape after WWI, fell far behind schedule. Some main lines could not withstand the twenty metric ton axle loads of the BR 01 especially those in the flat country in northern Germany.

So it was decided to build another Pacific locomotive which would have an axle loading not to exceed 17.5 tons. Initially, manufacturers were asked to develop a locomotive with compound expansion cylinders but, as Prussian influences won, a simple expansion design, similar to the BR 01, was selected. The main differences between the BR 01 and the new loco-motive were in boiler diameter, (1.70 m instead of 1.90 m), thickness of frame plates, (80 mm instead of 90 mm), and smaller diameter cylinders, (570 mm instead of 600 mm). Known as the BR 03, she was remarkably sleek. The BR 03 was 8% lighter than the BR 01 and, as she proved to be a fast flyer on the track, she underwent many streamlining trials. A total of 298 examples were ordered from Henschel, Krupp, Borsig, Schwartzkopf and other German manufacturers, production finally ending in 1937.

The BR 03 family was badly damaged in WWII; only 150 BR 03s remained in West Germany after the war and, even counting 70 others in East Germany, there were more than one quarter of the total which never saw their homeland again. While 35 survived in Poland, tracing those in other eastern occupied countries proved to be impossible.

During the 1950s and 60's new boilers were fitted to the remaining BR 03s in both East and West Germany. With their performance considerably enhanced by this modification, the BR 03 lived on until the end of steam operation in Germany.