The Welsh Hillman was thought to have been descended from ancient Welsh herding dogs. It was possibly the oldest Welsh sheepdog, and may have been the descendant of the old gellgi or "Welsh wolfhounds" used around 1,000 years ago. Some sources, without any obvious evidence, suggest it was crossbred with similar dogs seen in North Africa.
It was a large but rangy dog, up to around 25 inches in height, and described as "fast and fearless", with an appearance not unlike a lighter-built German Shepherd. The ears were pricked. The coat was usually of a light fawn, sandy or red-gold colour with a black saddle, white chest, white on the legs and tip of the tail and a blaze on the face. Blue merle dogs were also occasionally seen.
The breed was uncommon in modern times. C. L. B. Hubbard, writing in 1948, described it as "almost extinct" and "scarcely ever seen working today". The last known Welsh Hillman, "Jess", was purchased in 1974 from a hill farm near Hay-on-Wye by the author and broadcaster Jeanine McMullen, and was spayed before her owner realised her rarity.
- Vesey-Fitzgerald, B. S, (1948), The Book of the Dog Nicholson & Watson, p.684
- Carpenter, B. The Shepherd's Dogge, Fall 1994: see Welsh Sheep Dog Archived 2013-02-07 at the Wayback Machine, The Border Collie Museum
- Wildhagen, P. History of the Australian Shepherd Archived 2012-02-17 at the Wayback Machine, ASCA Yearbook, 1977
- Hubbard, C L B. Dogs In Britain, Macmillan, 1948
- Seis, C. Working Dogs: Training for Sheep and Cattle, Elsevier, 1996, p.11
- McMullen, J. A Small Country Living Goes On, W W Norton, 1991, p.137