Pure race espagnole
Jerez is the original home of the Carthusian sub-strain of the Andalusian horse breed, known as the "Caballo cartujano" in Spain. In the latter 1400s, the Carthusian monks began breeding horses on lands donated by Álvaro Obertos de Valeto for construction of the Charterhouse of Jerez de la Frontera ("la Cartuja de Jerez de la Frontera"). When the Spanish Crown decreed that Spanish horse breeders should breed their Andalusian stock with Neapolitan and central European stock, the monks refused to comply, and continued to select their best specimens to develop their own jealously guarded bloodline for almost four hundred years.