Said to have originated in the British Isles, the name "bull" was applied because of the dog’s connection with bull baiting. The original bulldog had to be ferocious and courageous, and almost insensitive to pain. When dog fighting became illegal in England, fanciers set to the task of preserving the breed by eliminating the fierce characteristics. Within a few generations, the Bulldog became one of the finest physical specimens with an agreeable temperament.  (Source: American Kennel Club)