What two breeds make a English bulldog?

Unlike a lot of dogs, the English bulldog was not created by crossing two specific Dog Breeds together but was rather developed by crossing a variety of different dogs in an attempt to make the ultimate bull-baiting dog. What dog-breeders would look for in dogs was short snouts, strong jaws, muscular bodies, dogs that were low to the ground, and had a tenacious demeanor. Dog breeders would breed together these dogs with the desired traits until the ideal bulldog was created. These pre-bulldogs are not well known, although there is a suggestion that they may of descended from mastiff-type dogs.