Star introduced their first compact tilting-barrel pistol (the Model D) in 1922. The Spanish military was interested in something along these lines, but the Model D was intended to be a civilian pocket-carry gun, and was just too small for military use. What was needed was something still compact, but with a full-size grip – a gun that could serve as a pilot’s emergency pistol, for instance. Star developed this as the Model S, still chambered for the .380ACP cartridge, but with an 8-round capacity.
The Model S was introduced in 1935, but the Spanish Civil War the next year prevented production from really beginning until 1939. The Model S at that point does get a lot of Spanish military and police interest, including a contract from the Spanish Air Force, which this pistol is an example of (manufactured in 1945). They were purchased by a number of foreign militaries as well, and served with Spanish police forces into the 1990s – despite most people thinking they were just a civilian pistol.