The Persian is the oldest breeds of cat. In Britain, it is called the Longhair or Persian Longhair. A Persian without an established and registered pedigree is classed as a domestic longhair cat.
The first documented ancestors of the Persian were imported from Persia into Italy in 1620 by Pietro della Valle, and from Turkey into France by Nicholas-Claude Fabri de Peiresc at around the same time. From France they soon reached Britain. The longhaired cats from Persia were interbred with Turkish Angoras. Their appearance then differed greatly from today's standard. Hundreds of years of selective breeding made Persians cobbier cats with drastically shorter muzzle. It's not clear when longhair cats (in general) first appeared, as there are no African Wildcats (believed to be ancestors of domesticated cats) with that kind of fur. There have been claims that the gene responsible for long hair was introduced through hybridization with Pallas cat. Recent research however refutes this theory.