John "Jack" Russell, a 19th-century clergyman, developed the breed to hunt foxes in the English countryside. He valued their energy, courage, and ability to go to ground (enter fox burrows) to flush out foxes. They were smaller than traditional terriers, allowing them to navigate tighter spaces.
The Parson Russell Terrier is still known for its hunting instincts and is often used for hunting foxes, rabbits, and other small game today.