In 1919 the Armstrong Whitworth Development Company took over the Siddeley Deasy Company and Armstrong Siddeley Motors Ltd was formed. Their first cars set the standard for Armstrong Siddeley – solidly built, dependable and comfortable with their trademark the V-shaped radiator and Sphinx mascot.

The Sapphire, a big, traditional saloon, was launched in 1952 and had Connolly leather, power assisted steering and a preselector or automatic gearbox, although this particular car has a manual gearbox.

During the late 1950s Armstrong Siddeley found it increasingly difficult to compete with other luxury car makers, such as Jaguar. The last of its cars emerged from the Coventry factory in 1960 and the company was left to concentrate on its aircraft business.