When the Spaniard explorer Hernando de Soto and his numerous followers introduced European mastiffs and hounds to the American continent in the 1500's, early ancestors of the Catahoula Leopard Dog started to take shape. Through crossings with the dogs of the American Natives and the Red Wolf, as well as the influx of some French working breeds, most notably the Beauceron, in the 1680's and later in 1750's, the Louisiana Clearwater Mastiff, as the breed was known in the past, developed into a resilient and versatile worker, highly praised for its hunting and guarding abilities. The Catahoula Leopard Dog was declared the official State Dog of Louisiana in 1979, where it enjoys immense popularity to this day. The "Leopard" misnomer is a reference to the breed's spotted patches on its coat and not the popular myth regarding the supposedly leopard hunting history, perpetuated by both some ignorant and overzealous breeders and fanciers.

A breed of legendary versatility, the modern Catahoula Leopard Dog is still used as a property guardian, hunting dog, livestock herder and protector, as well as a loving family pet. This muscular, athletic cur can be quite stubborn, but is still more trainable than most hunting dogs. There is a variety of types among the Catahoulas, from lean and narrow-headed dogs to those that are stocky and somewhat mastiffy in head-type. Bobtailed dogs are accepted, too.

The coat is short, smooth and flat, coming in a variety of trademark merle colorings, usually blue, red, brown and grey, as well as black-and-tan. Average height is around 24 inches.