The Clun Forest originated in the mountainous district of South West Shropshire in England, adjoining the Welsh Border, and are the most numerous sheep of the Marshes of Wales. They take their name from the ancient market town of Clun. Some authors attribute the breed to a combination of Hill Radnor and Shropshire, with Kerry Hill breeding also introduced in about 1865.
Cluns are considered a hardy, moderately prolific, long lived, easy care breed of medium size. They are a relatively new breed in the United States, first imported in 1959. Clun Forests are darkfaced with no wool on the head and legs. They should have a long, clean face of dark brown color, free from wrinkles. Ears of short to medium length, set well on top of the head. Bold, bright eyes. Top of head nicely covered; free from dark or black wool.

The Clun fleece is a short, close-textured wool of consitently high quality, with a spinning count of 58 and a high degree of elasticity.