Additional information (Wiki):In its native England, the Kennel Club (UK) recognizes the Manchester Terrier in the Terrier Group and the closely related English Toy Terrier (Black and Tan) in the Toy Group.

In North America the Manchester Terrier is divided into two varieties. The Toy Manchester Terrier was originally recognized as a separate breed in 1938, bred down in size from the Manchester Terrier. The Toy Manchester Terrier weighs less than 12 pounds and has naturally erect ears, never cropped. It is placed in the Toy Group by the Canadian Kennel Club and the American Kennel Club, although the Manchester Terrier is placed in the Terrier Group. The Manchester Terrier non-toy variety weighs 12 to 22 pounds and has 3 allowable ear types (naturally erect, button, or cropped). Other than size differences and ear type, the Manchester Terrier and the Toy Manchester Terrier have the same over all appearance, and since 1958 have been varieties of the same breed.

The early 1800s saw times of poor sanitation in England. Rats soon became a health menace and rat killing became a popular sport. John Hulme, enthusiastic devotee of the sport of rat killing and rabbit coursing, crossed a Whippet to a cross bred terrier to produce a tenacious, streamlined animal infinitely suited to the sport. (Perhaps the Whippet influence explains the unusual topline of the Manchester still required today). This cross proved so successful that it was repeated, resulting in the establishment of a definite type—thus the Manchester Terrier was born.