The King is a breed

Breed

A breed is a group of domestic animals or plants with a homogeneous appearance, behavior, and other characteristics that distinguish it from other animals or plants of the same species. Despite the centrality of the idea of "breeds" to animal husbandry, there is no scientifically accepted...

 of pigeon

Domestic Pigeon

The Domestic Pigeon was derived from the Rock Pigeon. The Rock Pigeon is the world's oldest domesticated bird. Mesopotamian cuneiform tablets mention the domestication of pigeons more than 5,000 years ago, as do Egyptian hieroglyphics.Research suggests that domestication of pigeons was as early as...

 developed over many years of selective breeding

Selective breeding

Selective breeding is the process of breeding plants and animals for particular genetic traits. Typically, strains that are selectively bred are domesticated, and the breeding is sometimes done by a professional breeder. Bred animals are known as breeds, while bred plants are known as varieties,...

 primarily as a utility breed

Utility pigeon

Utility pigeons are domesticated pigeons bred for a source of meat called squab. Squabs have been used as a food by many nations for centuries. They were selected as birds that would breed and grow quickly...

. Kings along with other varieties of domesticated pigeons are all descendants from the Rock Pigeon

Rock Pigeon

The Rock Dove or Rock Pigeon, is a member of the bird family Columbidae . In common usage, this bird is often simply referred to as the "pigeon"....

 (Columba livia).
The breed is known for large size and suitability for squab

Squab (food)

In culinary terminology, squab is a young domestic pigeon or its meat. The meat is widely described as tasting like dark chicken. The term is probably of Scandinavian origin; the Swedish word skvabb means "loose, fat flesh". It formerly applied to all dove and pigeon species, such as the Wood...

 production.
The breed also has a variety bred for exhibition purposes at pigeon shows. It is called the Show King to distinguish it from the purely utility variety.