Despite its name, the Staffordshire Terrier's ancestor (Bull and Terrier) was first bred in the nineteenth century in Birmingham, West Midlands, rather than in the English county of Staffordshire where it was then later bred. The early ancestors of this breed came from England where, until the first part of the 19th century, the Bulldog was bred. Bulldogs pictured as late as 1870 resemble contemporary American Staffordshire Terriers to a greater degree than present-day Bulldogs. Some writers contend it was the White English Terrier, Fox Terrier, or the Black and Tan Terrier that was crossed with the Bulldog to develop the Staffordshire Bull Terrier; all three breeds shared many traits, the greatest differences being in color and spirit. The cross of Bulldog and Terrier was called by several names, including Bull-and-Terrier Dog, "Pit Bull Terrier" (Bull terrier used to fight on pit), or Half and Half. Later, it assumed the name of Staffordshire Bull Terrier in England. These dogs began to find their way into America as early as 1850. It became a new breed and was recognized by the United Kennel Club in 10 February, 1898, with the name American Pit Bull Terrier. In 1936 some pit bulls were accepted for registration in the American Kennel Club (AKC) Stud Book as Staffordshire Terriers with a new standard and purpose, belonging to the terrier and molosser groups. The name of the breed was revised January 1, 1969 to American Staffordshire Terrier; breeders in the United States had developed a variety which was heavier in weight than the Staffordshire Bull Terrier of England. The name change was to distinguish them as separate breeds.
The breed's popularity began to decline in the United States following World War II. In 2013 the American Kennel Club ranked the American Staffordshire Terrier as the 81st most popular purebred in the United States.