From the Colby Pit Bull Line to the Staffordshire Terrier: The True Protagonist - Colby’s Primo

In the early 1930s, the American Kennel Club (AKC) decided to recognize a new breed in order to dissociate the American Pit Bull Terrier from blood sports and pit fighting and to move beyond its image as a pure game dog. The pivotal dog that served as the bridge between the APBT and the Staffordshire Terrier was Colby’s Primo, a direct descendant of the Colby line registered under:

American Kennel Club - AKC 641-443

United Kennel Club UKC 233-460

American Dog Breeders Asocciation ADBA 500-01

Colby’s Primo, born in 1889 at John P. Colby’s kennel, embodied the three pillars of the Colby tradition in his very build: gameness, sound structure, and a balanced temperament. With a medium frame, well-defined musculature, and a broad head, Primo epitomized the original “pit bull” type that, after the founding of the Staffordshire Terrier Club of America in 1936, was presented to the AKC as a Staffordshire Terrier.

The creation of the Staffordshire Terrier Club of America sprang from the desire to preserve the hallmark traits of the game dog while distancing the breed from the stigma of pit fighting. The new Staffordshire standard drew directly on the conformation of Primo and other Colby dogs: medium size, athletic muscle, a powerful bite, and a temperament combining courage with sociability. When the AKC registered Colby’s Primo under the Staffordshire name, it marked the first official entry of a “pit bull” into the show ring under that designation.

This instructive chapter shows how, thanks to John P. Colby’s vision and the American Pit Bull Terrier Colby’s Primo, a pure game-bred dog could be transformed into a recognized show breed without sacrificing its functional essence. Rather than importing new bloodlines or inventing a new name, breeders built upon Primo’s proven genetics to lay the foundation of the Staffordshire Terrier, preserving both its working heritage and its adaptability to family life.

Even today, any Staffordshire Terrier pedigree will often cite Colby’s Primo and his ancestors Colby’s Brandy and Colby’s Mable. This case demonstrates how a single breeding decision—based on rigorous criteria of gameness, conformation, and temperament—can redefine the course of an entire breed, turning a century-old pit bull lineage into the cornerstone of an internationally recognized standard.

Modern Staffordshire Terriers still carry Colby genetics in their pedigrees; trace any line long enough, and you will find your way back to a John P. Colby American Pit Bull Terrier.