However, The conformation of the Andalusian horse started in the classical Greek era with the morphological design of an ideal proportion for equine movement and the search for nobility.  These characteristics were bred in Andalucia throughout the Medieval Age. The ancestors of the PRE, the horses of the Conquistadors were brought to American with the Spanish as early as 1492. They were seasoned and hardy fighting machines, but not completely the Pure Spanish Horse we know today.
The PRE bred is generally considered to have been created from 1567 to 1600 by King Filipe II of Spain. He was attempting to breed the perfect Baroque riding horse for the Nobility of Spain and Europe. In that he succeeded and his efforts have never been surpassed.
But how did the PRE arrive in the United States. To tell this story marries the factual and the romantic. Anecdotal evidence refers to how the famous 19th century lithographers, Currier and Ives were mesmerized by the beauty of the Spanish Horse. During the years of the production of the now familiar Currier & Ives works, the Spanish Terry Stud gifted Steven Currier with a number of PRE horses as a tribute to his art. Images of these horses used in the lithographs immortalized forever the rounded coup and beautiful face of the horse we all love.
Perhaps a more formal historical report can be taken from importation logs, which record the few Andalusian horses being brought into the US in 1964, 1966 and the 1970’s.
Repeated outbreaks of African Horse Sickness occurring in Southern Europe along with the rarity of these horses even in Spain kept the imported numbers small and intermittent. Anyone wanting a PRE had to buy from within the U.S. or go through a very expensive importation process from Mexico or Costa Rica. The famous stallion Legionario III came to Mexico in 1970.
African Horse Sickness appeared to be controlled around 1964 and the embargo on the exportation of the PRE was lifted. However another outbreak of the disease occurred in 1987 and all Spanish horses were required to be vaccinated and branded with an X on the shoulder. None of these horses could be exported. In the time gap between 1987 and the early 1990’s there was an interruption of bloodlines and the registration process. Consequently when importation began again in the 1990’s new bloodlines and Spanish breeders never seen before in the U.S. were introduced.
In 2009 there were only about 8,500 Andalusian horses in the United States; worldwide, less than 30,000. However by 2011 the number of registered Andalusians had risen to more than 185,000 worldwide with 15% (27,750) outside of Spain a large portion of these being in the United States.
A number of breeding farms have been established in the United States and there are currently several organizations supporting the breed. The oldest American Registry for the PRE, the PRE Mundial is operated by the Foundation for the Pure Spanish Horse. The Registry honors the traditions of the Cria Caballar and the Spanish Military that had the responsibility for the purity and recording of the breed in Spain for over 100 years.
Half Andalusians are also registered and hopefully this Royal breed will continue to contribute grace and beauty to the horse world.
 Juan Carlos Altamirano, History & Origins of the Pure Spanish Horse