During the Russo-Japanese War, the Imperial Japanese Army captured the southern portion of the Russian-owned Chinese Eastern Railway. The Japanese converted the lines under their control to Japanese 1,067 mm gauge, and sent 187 Class 2120 locomotives to the newly established South Manchuria Railway (Mantetsu) in 1905. However, in 1908, Mantetsu completed the conversion of its lines to standard gauge, rendering these locomotives useless. Five were sent directly to the Taiwan Government Railway, and the rest were returned to Japan. The Taiwan Government Railway eventually received a further ten, where they became class CK80.
