The traditional sport of hunting the "gamecock" is the foundation of the word "Cocker". The term "Cocker" denotes those spaniels which were used for hunting this bird. Many years ago hunting dogs were classified according to size. Those over 25 pounds were classified as Field Spaniels and those under 25 pounds were classified generally as Cocker Spaniels. Selective breeding of Spaniels and other hunting breeds in the nineteenth century began to distinguish and discriminate between the different types of Spaniels.

The Cocker spaniel was classified as a separate breed by the English Kennel club in 1892 and by 1946 in the United States two different "Cockers" were classified, the American Cocker spaniel and the English Cocker Spaniel. The two breeds diverged in several ways. This breed is notably the dog which retains a strong hunting instinct. The muzzle of the English Cocker is longer with less stop than that of the American Cocker Spaniel. The body is square, in contrast to the American Cocker which presents a sloping back and exaggerated rear angulation.

The English cocker is essentially a hunting dog and the form reflects the function. The English Cocker's body should present well sprung ribs for endurance in the field and a steady gait which is balanced and not overly "flashy" as is the picture which is presented by the American Cocker Spaniel's exaggerated movement. The tail is docked and the tail set of the English Cocker is slightly lower than that of the American Cocker, another important distinction between the two breeds.

The coat is longer and this can present a difficulty in the field, regular grooming and some trimming is necessary for neatness. The Spaniel ear is always long and heavily feathered, the hairs on the ear being much longer than the ear leather itself. The long drooping ears of the typical Spaniel are said to act as a means of sweeping the scent forward towards the muzzle when the dog is hunting.

When hunting the English Cocker is a steady and reliable hunter, aggressive and thorough. Its small size allows it to get into the thickets and brambles with ease and scare up the birds. The movement of the cocker should be long and reaching, with incessant tail action. It is typically a flushing dog, although it can be useful also as a retriever.

Both Cockers have a merry disposition and happy character, however the English Cocker appears most often to have a more solid and stable disposition, less stubborn in nature and easily trained. This is a smart dog which is inquisitive by nature and should have no timidity.

The dog is an eager hunter and very trainable, a faithful dog who works for his master as a companion and partner in the field and prefers the human companionship to that of other dogs. The English Cocker does not make a good kennel dog, needing to be with people is part of its nature and it is a reliable and affectionate pet and strong and capable hunting companion.