The bullmastiff, the original “Gamekeeper’s Night Dog,” was developed as a guard to protect English estates from poachers in the late 1800s. The breed was recognized as purebred in England in 1925, and ten years later in the United States in 1935. Today’s modern bullmastiff is an agile and athletic dog who is sound in temperament and body. He is a dependable family member and loyal protector. He is fearless and confident, yet docile. Males range from 25-27 inches in height and 100-130 pounds in weight. Females are 24-26 inches in height and weigh between 100 and 120 pounds.