Old English Bulldog
When bull-baiting became popular in England due to the shortage of bears, bull-baiters soon realized that large fighting dogs were built too heavy and too slow for this type of combat. When fighting a bull, dogs were trained to grab onto the bull's nose and pin the bull's head to the ground. If the dog failed to do this, the bull would fling the dog out of the ring with its horns. The British therefore decided to selectively breed fighting dogs for shorter legs and a more powerful jaw. These efforts resulted in the Old English Bulldog.