There is some argument as to whether or not the Carthusian is its own breed of horse, or just a variation of the Andalusian or PRE horse. This is why they are also known as Carthusian-Andalusians. They get their name from the sect of monks, the Carthusians, which bred the horses from the early 1700s to the early 1800s. The monks didn’t survive, but the horses did, although they are now extremely rare.
Areas near Madrid were considered prime horse breeding areas by the Spanish nobility. In the late 1600s, Andres Zamora entered the Spanish cavalry. His mount was a stallion by the name of El Soldado. When his time in cavalry ended, El Soldado parted ways with Zomora. He and his brother Diego became blacksmiths.
Legend has it that one day Andres found a poor old horse being forced to haul firewood. That horse was El Soldado. Andres immediately bought the stallion. The stallion covered two mares and then died. The only colt produced was a grey with warts under his tail named Esclavo, who was later sold to a breeder in Portugal. This became the foundation sire of the Carthusians.
In 1736, a horse breeder named Don Pedro Picado owed a lot of money to the Carthusian monks at Jerez monastery. He gave some daughters of Esclavo to the monks. The monks realized they had been given a gold mine. They only put the mares to the best studs they could find and kept up a stringent breeding program for 100 years. When the Spanish nobility tried to force cross-breeding through a royal decree, the monks promptly hid the horses.
When Napoleon conquered Spain, he took most of the Carthusians, which promptly died in battle. The monks would be disbanded in 1835 and the horses bought by private breeders.
The Carthusian is practically identical to the Andalusian, except for some small differences. The most desired Carthusians are grey and have warts under the tail like Esclavo. Some horses also have strange hard bumps over the eyes similar to those seen in the Moyle horse. These bumps also could appear in the middle of the forehead. These were once thought to be horns but are known as frontal bosses (similar to what giraffes have). Legend has it that Esclavo also had these horns.
Carthusians are a little smaller and lighter in build than the average Andalusian. They average 15 hands high (a hand being four inches), while Andalusians average 15.2. However, Carthusians and Andalusians can both grow to 16 hands high on occasion. The profile of the head is straight while the Andalusian is often convex. Carthusians and Andalusians have abundant manes and tails, small ears, wide eyes, wide nostrils and deep chests.
International Encyclopedia of Horse Breeds. Bonnie Hendricks. University of Oklahoma Press; 1995.
Simon & Schuster’s Guide to Horses & Ponies. Maurizio Bongianni. Simon & Schuster; 1988.
Storey’s Illustrated Guide to 96 Horse Breeds of North America. Judith Dutson. Storey Publishing; 2005.
The Official Horse Breeds Standard Book. Fran Lynghaug. Voyageur; 2009.