Although not certain, it's widely believed the breed descended from molosser dogs brought to Spain from Sumeria and Assyria by the Phoenicians over 3,000 years ago.
About the Pyrenean Mastiff
Pyrenean Mastiffs are ideal for guarding rural properties and people. These easy-to-train dogs are friendly, calm, noble and especially intelligent.
Strangers will be met by a brave and ferocious dog that stands its ground come what may; other dogs will meet a good-natured creature that is fully aware of its strength. Pyrenean Mastiffs are accomplished fighters if need be, drawing on all the skills they have acquired as a breed in centuries of combat with wolves. Their bark is deep and low, their expression alert.
Source: key facts and characteristics sourced from Fédération Cynologique Internationale (FCI)