The .38 caliber family of revolver cartridges has a long history, and the origins of the .38 Special lie in the .38 Long Colt cartridge (in its turn a modified version of the .38 Colt used in old metallic cartridge conversions of Colt cap and ball revolvers).

During the Filipino-American war, the Moros warriors used to work themselves into a frenzy for an extreme adrenaline rush that made the old cartridge insufficient in terms of stopping power, so that something more performing was clearly needed, and needed fast.

The only way to increase the power of a black powder cartridge was to increase the powder load and, since the load completely filled the case, the case itself had to be lengthened from 1.031” (26.2 mm) to 1.155” (29.3 mm), for an additional 3 grains of powder, significantly increasing the ballistic performance of the new cartridge over that of its predecessors.

Having been developed by Smith & Wesson, the new munition was dubbed the .38 Smith & Wesson Special or .38 Special for brevity, to clearly differentiate it from its older, Colt parent cartridge (note: firearms chambered for the .38 S&W Special can use .38 Colt and .38 Long Colt cartridges but not, ironically, .38 S&W cartridges, these being of an incompatible design).

Born at the end of the black powder era, the .38 Special was soon converted to use smokeless powder, and its good balance between terminal ballistics performance, accuracy, and mild chamber pressures and recoil still makes it one of the most popular revolver cartridges.