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The Mastiff is a dog breed that is quite ancient. From the days of Caesar to the Middle Ages to World War II, the breed has developed and splintered into various mastiff types. The modern Mastiff's large and domineering appearance may be quite intimidating, but the breed is actually quite gentle and very loyal.

Physical Characteristics

The Mastiff exudes dignity and grandeur. It is heavy boned, slightly long, powerful and massive with good drive and reach. The Mastiff's protective double coat is comprised of a thick undercoat and a straight, coarse outer coat of moderately short length. This outer coat comes in various colors, including fawn, apricot, or brindle.

Personality and Temperament

Although the Mastiff does not show much emotion, it is good-natured, easy going, incredible gentle, and very loyal, making it a perfect house dog.


The Mastiff can be kept outdoors, but not in hot or humid climates. Also, in order to fulfill its function as a devoted guardian, it should be allowed to live indoors. It requires minimal coat care and moderate exercise daily, usually in the form of a walk or game.


The Mastiff, with a lifespan of about 9 to 11 years, suffers from minor health conditions like osteosarcoma, elbow dysplasia, and cystinuria, or major conditions like canine hip dysplasia (CHD) and gastric torsion. Some dogs of this breed may also suffer cruciate ligament rupture, cardiomyopathy, vaginal hyperplasia, allergies, and obesity. To identify some of these issues, a veterinarian may run hip, thyroid, elbow, eye and DNA tests on this breed of dog.

History and Background

The history of the Mastiff is a bit muddled due to the confusion between this breed and the ancient Mastiff group from which it originates, but the modern Mastiff breed is of relatively recent origin. During the reign of Caesar, mastiffs were employed as gladiators and war dogs, and during the Middle Ages, they were used as hunting and guard dogs. Still later, they were used for bear baiting, bull baiting, and dog fighting. These sporting events continued to be popular even when they were deemed cruel and were banned in 1835.

The modern Mastiff descended from these pit dogs, but also from noble lines, such as the famous Mastiffs owned by Sir Peers Legh, Knight of Lyme Hall under the reign of King Henry V. During the Battle of Agincourt in 1415, Sir Peers' mastiff stood by and protected him on the battlefield for several hours after he was wounded. In spite of the death of Sir Peers, his mastiff returned to his home and founded the origin of the Lyme Hall Mastiffs.

There is some evidence a mastiff was brought over to America on the Mayflower, however, the earliest documented entry of the breed did not occur until the late 1800s. Like many other dog breeds, World War II almost annihilated the Mastiff in England; fortunately, there were sufficient dogs in the United States to revive the breed. Today, the Mastiff is has become one of the most popular breeds in the U.S.

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