When Churchward was looking for a replacement for many older 2-4-0 locomotives in secondary service, he used the class 3150 2-6-2T tank locomotive as a basis. Since this exceeded the axle load on many routes due to its reserves, he developed the class 4300 tender locomotive. It had the 2-6-0 wheel arrangement and used many standard parts in the areas of cylinders, wheels and boiler. The standard No. 4 boiler had a superheater and was rated for 225 psi, but here it was only operated at 200 psi. 

Between 1911 and 1923 Churchward had several batches built in Swindon. In 1921 and 1922, due to Swindon's limited capacity, 35 were built by Robert Stephenson & Co., while a further 15 were assembled in Swindon from parts prefabricated by the company. This brought the total to 342. Eleven were used by the ROD in France during the First World War. Their sisters in Great Britain were very useful in a variety of services and could reach speeds of up to 70 mph or 113 km/h.

Churchward's successor Collett also had a total of 30 more locomotives of this class built in 1925 and 1932. In 1928, 65 were given extra weight on the leading axle to reduce wear on the winding roads in Devon and Cornwall, and were then designated the class 8300. Between 1936 and 1939, the first 100 older members of the class 4300 were withdrawn. Due to the war, the next withdrawals did not start until 1948 and the last locomotives survived until 1964. Two were preserved, of which 5322 in ROD livery was operational until 2014.