The Caste Motor Company Limited was founded in 1907 by two brothers, Laughton and Stanley Goodwin, in Kidderminster. They started as a garage with premises on New Road and soon opened a shop on Vicar Street as the spare parts department.
After seven year in business it gained popularity and esteem and in the 1914 Michelin Guide is was the only listed garage to be included for Kidderminster.
At the outbreak of war the garage went into production of munitions such as H. E. shells; depth charges; pistols; gun carriage hubs; and components for ABC Dragonfly engines.
The business grew with the additions of more premises, a spare shop on Broad Street in w:Birmingham and another shop in w:Worcester.
After the First World War Stanley Goodwin designed the Castle Three three-wheeled car. The body was designed to more like a four-wheeled car rather then the cycle-car image most often associated with three-wheeled cars. The engine used was a four cylinder side valve, water cooled, 1094cc Dorman engine, however later on this was superseded by a four-cylinder 1207cc, 9hp Peters engine.
Many problems associated with the model, particularly the transmission, stopped the manufacture of the model after 350 vehicles produced. In 1922 Stanley Goodwin designed a four-wheeled car called the Castle Four, but it was too late for production as the company cease trading. Birmingham City Council owns a Castle Four.
So far only two Castle Three cars survive a body shell was discovered in w:Brittany and brought back to England for complete restoration. How came to be in Brittany is a complete mystery. This vehicle now resides in The National Motor Museum at Beulieu. The other was discovered in Yorkshire and bought by the County Museum in Hartlebury.