The Romans were the first to classify dogs, which they arranged into three groups according to the purpose for which they were used:

• Class 1: Canis villatica or house dog. This category probably included all types used for human protection and the destruction of vermin around the villa.
• Class 2: Canis pastoralis or shepherd's dog
• Class 3: Venatici or sporting dog

Shepherd's or herding dogs can be further divided into groups including pastoral dogs, which can be any dog connected with rural life or used in the management of stock on pasture grazing; droving dogs, which encompassed a wide range of dogs each selected by the drover for its natural instincts to deal with the particular breed being transported; and herding or stock dogs which is any type of canine that has assisted or assists man in any given capacity with domestic livestock in general. From these groups come the many different sheepdogs, working sheepdogs, collies, and flock dogs. During one period around the 10th century peasants were only allowed to keep small dogs for the destruction of vermin. Hired keepers, shepherds and herdsmen were also allowed to keep their dogs, but all were required to be mutilated in some way to prevent poaching of the royal game. Some of these mutilations were quite severe, but the herdsman's dog was required only to have his tail docked, or cur-tailed, as it was felt this was sufficient to slow him down. The people tried to evade this law, but penalties were severe and the monies from these fines were a welcome source of revenue to the crown. When these laws became unworkable, the crown then levied a tax on dogs. Realizing that the peasants could not pay these taxes, nor could they live without the help of a dog for certain tasks, an exemption from tax for dogs used for a purpose was provided. The shepherd or herdsman's dog was still exempt from this tax if his tail was docked.

The word "Corgi" is either from the Welsh "cor" (dwarf) and "ci" (dog). The "ci" becoming "gi" by normal mutation resulting in corgi. Another interpretation is that of "cur dog" or "Cur". This interpretation can be dated back to one of the earliest dictionaries, to Wyllam Salesbury's "A Dictionary in Englyshe and Weslhe" London, 1574, where there is a reference to the "Korgi ne gostoc", that is, Corgi or curre dogge. (The use of the K rather than the C at that time was perfectly proper and eventually the K was no longer used interchangeably with the C.) The connection of the word "Corgi" with "Cur" has considerable historical support as there are many references to Corgwn (plural of Corgi - pronounced Corg’n, sound out like oxen) in many a cywydd (a song of praise) in the 14th and 15th centuries.

It must be understood that the term Cur was not used in a derogatory sense when applied to dogs, as we do today. It did mean a dog of low breeding, as distinct from the "superior kinds" of dogs, but generally it indicated a working type of dog as opposed to the sporting and luxury or ladies' lap dog. The Ancient Welsh Laws referred to three kinds of Curs: the Watch Cur; the Shepherd Cur; and the House Cur. The Cur was truly a very useful and well disciplined race. It is interesting to note that Iris Combe traces the origin of the Corgi back beyond its pastoral origins and connects it with the Nordic breeds. Through this connection, she traces them back to Neolitic times when islanders families lived on a diet of fish, sea-birds and their eggs, the soil on the islands being too shallow and poor for crop cultivation. Through this connection it can more easily be explained the use of the Corgi on the huge flocks of geese and ducks kept in Wales to supply the demand for fine feathers and liver for pate throughout Britain. It was well known that the Corgi was used as a heeler and a drover, especially on sheep and cattle. This could also explain the affinity many Corgis have for the water. Ms. Combe's connection of the corgi with the original role was that of a wildfowler's dog, on the cliffs and in the caves of the Welsh coastline, to supply the trade in seabird's feathers and eggs. The corgi or spitz types were used to work the caves and rock faces to hunt out live birds. The Scandinavians believe our corgi is descended from their Lundehund, one of the Spitz family group. The Lundehund has a similar ear carriage to the corgi, and the ears can be folded back so that ear canal can be protected against wind, sand or moisture. Another breed resembling the corgi in appearance is the Swedish vastgota-spitz, or Vallhund. Vall means farm or guard dog and he is in fact mainly a cattle dog from a particular Swedish province. There is a difference of opinion on the place of origin of the Vallhund. Some think that the original dogs brought to Sweden were the corgis, which over the centuries the Welsh had turned from bird dogs to cattle dogs. Others believe that the introduction of the Vallhund from Sweden helped in the evolution of the corgi as a cattle dog. Some evidence points to the Pembroke corgi and the vallhund sharing the same ancestry.

the corgi in Britain was used as a guardian of the farmyard and helped to collect the domestic fowls. With poultry wandering freely around the farmyard, there was always a risk of them being taken by predators, and the corgi could guard against this. They were also quite useful in gathering the flock so that they could be housed for the night. When the huge flocks of geese were reared in Wales as a source of income, they were always a problem to guard. Taking them to market was quite a chore, and the only way to get a large flock of these large, quarrelsome geese to market was to drive them along the road to the town holding the market. Corgis were unsurpassed in this task, and working in teams along roads they knew they could anticipate any moves for escape a flock might make. They were fairly silent workers, as too much noise would only serve to scatter the flock, yet they were strong willed enough to control any goose that lagged behind or strayed. Corgis could also take command of cattle in certain situations on the farms, but it was as market dogs they excelled. They still retain this easy adaptability to manage all different sorts of livestock, from poultry, cattle or pigs. On the whole they can be used for most any purpose on the farm, though as a sheep herder they are not as suitable as collies, corgis being too sharp and excitable for sheep. They have even been used as gun dogs on both feather and fur and they are most efficient ratters.

Welsh corgis were exhibited in the UK after WWI, but not a lot of progress was made in the breed until the formation of the Welsh Corgi Club in 1925, which at first catered only to the Pembroke owners. In 1926, the Cardigan Club was formed and eventually became the Cardigan Welsh Corgi Association. In 1928 Challenge certificates were granted by The Kennel Club. In 1934 the Kennel Club recognized both varieties as separate breeds, and owners were given the choice as to which breed they wished to have their dogs entered as - Cardigan or Pembroke. The acquisitions of Rozavel Golden Eagle, a Pembrokeshire Corgi for Princess Elizabeth in 1933 is what drew the public's attention on that breed more than on the Cardigan Corgi.