American Bulldogs descend from working bulldogs that settlers brought to the colonial South, where they caught loose cattle and feral hogs and guarded farms. The breed nearly vanished after World War II until John D. Johnson and Alan Scott revived it. Today's dogs range from the heavier, shorter-muzzled Johnson type to the leaner, more athletic Scott type, and many are a mix of both, usually mostly white and 60 to 115 pounds.
Many are devoted, affectionate and confident, with a protective streak and plenty of stamina. In Louisville, that means a securely fenced yard or a firmly held leash, since the countywide restraint rule applies off your own property. Early socialization and consistent reward-based training help a strong dog handle busy sidewalks and visitors. Every dog varies, and many dogs labeled American Bulldog are mixes.