Despite being called a "Spanish Greyhound", the Galgo is not truly a Greyhound. The lineages of the two breeds are different. However, in the last century or so, some breeders have cross-bred Galgos and Greyhounds in order to produce faster Galgos.

The Galgo Español (Spanish Galgo) or Spanish Greyhound is an ancient breed of dog, specifically a member of the sighthound family. The Galgo was named for the Gauls, who inhabited the Iberian Peninsula 400–600 B.C.E. The Galgo breed was probably a result of the dogs brought by the Gauls on their migration through the peninsula mixed with dogs brought by traders who did business with the Gauls.