The bulldog originates from Britain, their original purpose was to aid butchers in controlling savage bulls.  It was believed that the meat would result in being much more tender and nutritious after the bulls had been worked up by these dogs prior to butchering them.

The bulldog was developed with heavy bodies and short legs to keep out of the way of  the bulls horns, the wrinkles around the face were specific functions of keeping the blood from the bull out of the dogs eyes and nose.

It did not take long for man to use these dogs for their own entertainment in the cruel sport of bull baiting.  During these contests the dog would attach itself to the bulls nose.  The bulldogs jaw being undershot, enable the dog to attach with a vice like grip making it almost impossible for the bull to eject the dog. 

The bulldogs sheer determination and strength would eventually bring the bull to the ground. 

These powerful dogs were bred as pure fighting machines before bull baiting was, thankfully outlawed in 1835.