The Bullmastiff is a breed of large dog. A member of the Working Group, it is large and solidly built, with a short muzzle. The Bullmastiff shares the characteristics of Molosser dogs like it, and was originally developed by 19th-century gamekeepers to guard estates and immobilize poachers. The breed's bloodlines are drawn from the English Mastiff and Old English Bulldog; it was recognized as a purebred dog by the English Kennel Club in 1924. It is an athletic and muscular dog, yet docile and obedient, traits which have made the breed popular as a family pet.A Bullmastiff should be confident, yet docile. A Bullmastiff is courageous, extremely loyal to its family, calm, and loving. Bullmastiffs become intensely attached to their families.Bullmastiffs can get along with other dogs, though, like many animals it is common for males not to get along with other males. They also may get along with the family house cat but not with other strange animals. The Bullmastiff can get along extremely well with children provided the dog has been properly trained and socialized. Parental supervision must be maintained when they are with children; as with most large dogs, they may knock smaller children down accidentally.A Bullmastiff, because of its history, is a very independent dog, and likes to make its own decisions. However, with good training, a Bullmastiff will look to its owner for "permission" to act on its instincts. Early socialization and obedience training with all members of the family will teach the dog to look to them before taking action. They are very athletic and muscular, making them incredibly fast and agile.They were never bred for hunting purposes, and rarely show signs of aggression. The Bullmastiff is considered a sweet-natured breed, although potentially dangerous due to its great size and strength.