With the introduction of foreign breeds to the United States during the early part of the 20th century, the naturally pure bloodlines of these native shorthairs began to be diluted which resulted in kittens with a variety of coat lengths, body types, colors and temperaments. There were some that wished to preserve the natural qualities of this breed and admired the American Shorthair's sweet disposition and beautiful face. These early breeders started to selectively breed these cats using the finest examples of the breed working to retain the general appearance and loving temperament of the breed while improving the patterns and coat colors.

American Shorthairs were the first pedigreed breed recognized in the United States. Originally known as the Domestic Shorthair, in 1966 the name American Shorthair was chosen to better represent this American cat and differentiate this native breed from any other shorthaired cats.

In appearance, the American Shorthair is a strongly built, well-balanced, symmetrical cat with a look that indicates power, endurance and agility. They are medium to large in size with a solid body and wide chest with thick hind legs. Their heads are oblong in shape with a wide face, wide-set ears and round eyes. This breed is also known for its longevity and robust health. On average, American Shorthairs live fifteen to twenty years. Males are significantly larger than females sometimes reaching eleven to fifteen pounds in weight while mature females can reach eight to twelve pounds in weight.

These beautiful cats are very gentle and affectionate and make wonderful companions. Having a quiet, even temper, this breed is known for its amiability with children and other pet animals thus making them a very popular choice of pet. American Shorthairs are consistently in the top ten most popular breeds of cat. They are easily trained and are often found featuring in television, cinema and magazine advertising. American Shorthair owners not only admire the lovely looks of this cat, but also their quiet, loving disposition.

The American Shorthair has a short, thick, even coat that comes in a rainbow of colors and patterns which include solid colors, bi-colors, tortoiseshell or calico and tabby. The most popular American Shorthair color is the silver tabby with dense black markings set on a sterling silver background. Eye color may be gold, copper, green, hazel, blue, or odd-eyed (each eye is a different color), depending on the coat color.

By chance, a non-pedigreed shorthaired cat (or "Domestic Shorthair") might resemble an American Shorthair, just as another random-bred cat might look like a Siamese, Persian or Maine Coon. The difference, however, is that a pedigreed cat can consistently produce kittens of the same physical conformation, coat quality, and temperament, while a random-bred cat cannot. Years of selective breeding and the careful recording of many generations of cats guarantee that each litter of kittens will have specific qualities.