* Old English Bulldog: This breed is definitely a significant part of the Bull Terrier's lineage. The Bulldog contributed the breed's strength, tenacity, and distinctive head shape.
* White English Terrier: This breed, now extinct, is believed to have played a role in the development of the Bull Terrier. It was known for its white coat and spirited personality.
* Other Terriers: It's possible that other terrier breeds, like the Dalmatian or the Black and Tan Terrier, were also used in the creation of the Bull Terrier.
However, the exact mix of breeds and the timeline of the Bull Terrier's development are not completely clear. What we do know is that the breed was intentionally developed in England in the 19th century for bull-baiting and dog fighting, which were popular sports at the time.
It's important to note that the Bull Terrier, like many other breeds, has undergone significant changes since its early days. Through selective breeding, the breed has become much more refined and less aggressive, making it a popular companion dog today.