The Parson Russell Terrier / Jack Russell Terrier, first bred in the South of England in the mid-1800's.  To work the Red Fox, both above and below ground. The Parson Russell Terrier / Jack Russell Terrier originally ran with both horses and hounds as the hunt (field) ran the fox across the open country-side of Devonshire and surrounding Counties.  When the hounds ran a fox to ground, the terrier entered, his function was to either bolt the quarry or if unsuccessful at bolting, bay and hold the quarry until dug to.  If his job was successful, he bolted his quarry, the hounds would then take up the hunt once again.  If unsuccessful at bolting his quarry, the terrier man would listen, at times with ear to ground to determine where the terrier was  baying and holding. The terrier man would then dig down to him and either release, or dispatch of the quarry.
 

Everything about the Parson Russell Terrier / Jack Russell Terrier has fox hunting in mind; his conformation, character, attitude, and intelligence. He is of a well balanced, proportioned build, with straight legs and a narrow, flexible chest. He measures ideally between 121/2" - 14" in height. His jacket is Smooth, Broken or Rough, all of which should be, dense, harsh, and tight, to withstand the bitter cold elements of Winter work.  The jackets on Broken or Rough Parson Russell Terriers / Jack Russell Terriers should be straight, so as to give him the appearance of a Smooth from a distance. His height gives him the length of leg to follow the fox above ground.  His narrow chest, flexible frame and determination, lets him follow a fox into the den. He is tractable and bold, though cautious in temperament.  An independent, thinking terrier, accustomed to working along side his human counterpart.

The Parson Russell Terrier / Jack Russell Terrier is named after one of the most renowned of British huntsmen, Reverend John Russell, "The Sporting Parson" (1795 - 1883), whose passion for Fox Hunting, Hounds, and working terriers is legendary. John Russell and his associates, bred with care, uniform working terriers. Well balanced in height and weight.

After John Russell's death, the name "Parson Russell Terrier / Jack Russell Terrier" was misused to describe all manner and mixture of working and hunt terriers, many of which bore little, if any, similarity to Russell's own terriers. The mounted style of Fox Hunting in England had been hampered by expanding agricultural practices and the sport became expensive. Those without sufficient land or resource took to Fox and Badger digging for terrier sport. Terriers were carried to known sets and released down an earth to attack whatever they found, no horses or hounds required. These terriers were more aggressive than intelligent, and needed not the leg, stamina, nor common sense of the early Parson Russell Terrier / Jack Russell Terrier. The public came to know a "Parson Russell / Jack Russell" only as a game working terrier, regardless of shape or size.  Unfortunately, it was this kind of terrier; bull-headed, long-backed,  short-legged, prick-eared, frequently achrondroplastic and of questionable temperament, that was imported to North America incorrectly bearing the name "Parson Russell Terrier / Jack Russell Terrier" and who can be found all over the media today. Parson John Russell and his associates would not have recognized these terriers, not as Parson Russell Terriers or Fox Terriers, nor as a suitable dog for Fox Hunting, for indeed they are not.  

The first Parson Russell Terrier breed standard was drafted in 1904 by Arthur Heinemann, who founded the Parson Parson Russell Terrier Club in 1914. The standard calls for an overall proportioned terrier and accurately reflects the original Parson Russell Terrier / Jack Russell Terrier. This Parson/Jack type Russell Terrier was, and still is kept alive by sportsman throughout England and has been recorded throughout the years by well-know dog fanciers.