The Bullmastiff’s nickname is “The Gamekeeper’s Night Dog”. Breed was developed in England during the mid 19th century by gamekeepers for aristocrats. Because a poacher might face the death penalty if captured, they had nothing to lose when encountering a gamekeeper, so gamekeepers responded by breeding dogs big, swift, and brave enough to pursue and pin a man, without biting. To create bullmastiffs, they mixed mastiff and bulldog. The new breed was smart and biddable, not overly aggressive and big enough to scare any intruder, all while being a good family dog.