Although a man of the cloth, the "Hunting Parson," Rev. Jack Russell, was a passionate fox hunter of the mid-1800s and pursued the sport until his death at age 88. Fox hunters needed small dogs to roust the foxes who had escaped to ground. Many hunters employed smaller or shorter legged terriers, which had to be carried on horseback to the fox's lair. But the Reverend Jack liked a longer legged type that could follow the hounds on foot. He developed his own strain, based on a crossbred terrier bitch, "Trump," which he bought from a milkman.

How Russell continued with the breeding program was never recorded, but even modern proponents of the breed admit a certain amount of crossbreeding occurred. First, fighting bull-and-ierrier dogs were used to add the white color (easily differentiated by the hounds from the fox) and increase the aggression and tenacity. Unfortunately, this often resulted in a dog that silently killed the fox underground, thus spoiling the sport of the hunt for the others! Small "pocket" Beagles were used to temper this hard edge, as well as adding the tendency to give tongue. The result was a dog that was often one thought ahead of the fox.

Game to this day, a good Russell Terrier is still capable of going to ground. One owner described how her three JRTs chased a bull raccoon down a drain pipe near her home. When they hadn't emerged by the next morning, she had a backhoe brought in and started digging. The crew cut a ditch, reaching 300 feet, over the next 12 hours, and finally discovered the raccoon backed up against the cellar wall. Not only were the terriers none the worse for the ordeal, they were still jockeying for position with one another to get closest to the prey. It is not unusual for this breed to forego food, water and other creature comforts once it has the whiff of the quarry.

Although the Parson never used his dogs for the purpose, the JRT is also a plucky ratter. In 1977, an Englishman and his team of four Jack Russells took three tons of rats out of chicken farms in just one day! Another modern JRT owner gave this practical advice to a writer from Sports Illustrated to pass on to anyone planning to take part in this sport with their dogs: "If you take your terrier ratting, always wear slacks or breeches tucked either into your Wellingtons or into your socks so that the rats cannot run up your trouser legs or skirt. This happens far more often than one might imagine, and, although it may be excruciatingly funny to the rest of the party, it is no joke for you."