They go by type not breed. if the horse is of the right type they will use it no matter the breed.
The Calvary.
You're confusing Calvary (cricifixion locale) and cavalry (military group)
a horse
a black and white horse is called piebald
Black of course. That's why he was called the Black Horse of Napoleon
Pegasus was the flying horse. Bucephalus was Alexander the Greats favorite calvary horse.
a black MARE
it is a animal eg horse or elephant with a person on it
this is a fictional story of a beautiful black horse, but there must be horses out there that are called "Black Beauty"
a horse marked with black and white coat is known as a PieBald
Military on horseback were referred to as the Calvary.