Some evidence exists that the Mastiff (also known as the Old English Mastiff) came to America on the Mayflower. The Mastiff is an excellent guard dog. Its owner must however handle it very decisively: otherwise it can become dangerous. In medieval times, they were used as guard dogs. Mastiffs later stepped into the arena of dog fighting, bull baiting,  and bear baiting. The Mastiff is loyal to his family and good with children.