The spanish mastiff, or mastin espanol as it's called back home in Spain, like many other breeds has a past consisting of few documented facts, and many theories. Large mastiff-like watch and cattle dogs have been around for a very long period, known in Spain even over 1500 years ago. Over time, these mastiffs spread over the peninsula, developing into among others the spanish mastiff. The breed is sometimes known as Extremadura or La Mancha, kept mainly as a cattle guarder. The breeders looked for dogs that would not hesitate for one second whether to attack a wild wolf or not. Since the 1900s, the breed has periodically been very popular in spanish shows, but the standard was not written until 1946.

The spanish mastiff should appear large, compact and majestic. It should have a powerful, rectangular bodyshape, with a topline that is more or less straight. The legs are thick with compact paws. The head should have a slightly rounded forehead, with long muzzle and deep lips. Despite its size, the spanish mastiff should move gracefully. It is strong, brave and an excellent watch dog.