In World War II the Southern Railway, usually making most of its revenue with commuter traffic, found itself on the front line. So they urgently needed a goods locomotive that could be built cheaply and quickly, saved strategic resources and was powerful. Oliver Bulleid decided to build a locomotive with the traditional 0-6-0 wheel arrangement, but more powerful than all others. He also removed all parts which were not essential for operation, but incorporated some innovations in the basic structure.

The most prominent feature of the Q1 was the boiler that had plain and flat side walls, which resulted from the fiberglass insulation and enabled them to use coach washers. The wheels with a diameter of 5 ft 1 in were of the Bulleid Firth Brown type also found on the Pacifics of the same designer. The cylinders were on the inside and had generous steam passages. The chimney was fitted with a five-nozzle blast pipe. All in all, they were still so light that they could be used on almost the entire Southern network.

20 locomotives each were built at Brighton and at Ashford. They were the most powerful 0-6-0 ever built in Britain and were assigned power class 5F when taken over by British Railways in 1948. Due to their unconventional look, they got several nicknames like “Ugly Ducklings”, “Coffee Pots” or “Frankensteins”. Nevertheless, they fulfilled their tasks and even hauled passenger trains on secondary lines. They were withdrawn between 1963 and 1966 and today only the first locomotive numbered C1 is preserved. It ran for the last time in 2000 and is now located in the NRM at York.