Preserved Castle 5051 is today recognised as Drysllwyn Castle, but the name was carried by three members of the class at different times.
5051 was named Drysllwyn Castle when it entered service in 1936, but was renamed Earl Bathurst in 1937, after the proposed use of Earls' titles for the 90xx 'Dukedog' class met with disapproval due to the 'new' locomotives' elderly appearance.
The next batch of Castles received the existing and now spare Castle nameplates, 5076 appearing 1938 as Drysllwyn Castle. This engine carried the name until January 1941, when several Castles were renamed to commemorate the recent aerial victory of the Battle of Britain, 5076 being given the name Gladiator from the RAF Gloster Gladiator aircraft.
The nameplates remained spare again until the last batch of Castles to be ordered by the GWR was being constructed. 7018 received the name Drysllwyn Castle on completion in May 1949 and was the longest holder of the nameplates, carrying them until withdrawn from service in September 1963.
5076 Drysllwyn Castle was completed in August 1938 and sent new to Exeter shed.
During WW2 the GWR patriotically renamed several Castles, featuring the names of RAF aircraft taking part in the Battle of Britain. 5076 was renamed Gladiator in January 1941.
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