The Spanish mastiff is thought to have existed for thousands of years. Mastiffs were working as livestock guardian dogs when the
Romans arrived on the
Iberian Peninsula. In
medieval times, this dog accompanied the herds of
sheep and
goats crossing from northern to southern Spain, defending cattle from attack by
wolves and other predators. The mastiff had the protection of chunky metal necklaces with skewers. Its function was primarily protective, unlike its fellow Carea dogs, whose function is grazing, driving the herds in response to indications of the shepherd. In some places it is known as
perro merinero when it accompanies sheep of the
Merino breed. The first breed standard of the Spanish Mastiff was made by the
FCI in 1946. In 1981 the Asociación Española del Perro Mastín Español was formed, who organized a breeding program looking for the kind of large and strong mastiff of the past times, and drafted a new breed standard focused on recovering the old cattle dogs, fit as pets, and as guard dog and defense. ==Appearance==