It is part of the Northern European short-tailed sheep group, and it is closely related to the extinct Scottish Dunface.

[2] Although Shetlands are small and slow-growing compared to commercial breeds, they are hardy, thrifty, easy lambers, adaptable and long-lived.

Up to the Iron Age, the sheep of the British Isles and other parts of northern and western Europe were small, short-tailed, horned only in the male and variable in colour.

[4] The Dunface died out on the mainland, Scotland, in the late nineteenth century,[5] leaving its descendants limited to a few islands, including the Shetland Isles.

[6] By the early twentieth century, the Shetland was perceived as threatened by cross-breeding, leading to a decline in wool quality.

[8] A Shetland ram was kept by United States President Thomas Jefferson for several years in the early nineteenth century.

[11] Other importations were made at the beginning of the twentieth century most notably to Mrs. W.W. Burch of Coopersville, MI (wife of the Editor of the American Sheep Breeder at the time), and Mr. L.V.

[12] Since then, a North American Shetland Sheep Registry has been established, and there are now thousands of the breed in the region.

A distinguishing feature of northern short-tailed sheep is the short, fluke-shaped tail, broad at the base, tapering to a point, and covered towards the tip in hair, not wool.

[15] Eleven main colours are recognised by the breed association (most including many different shades): light grey, grey, white, emsket (dusky bluish-grey), musket (light greyish-brown), shaela (dark steely-grey), black, fawn, moorit (reddish brown), mioget (honey-toned, yellowish-brown), and dark brown.

[8] They include: Like other "primitive" breeds, the ewes are highly seasonal, becoming fertile in October and November (in the Northern Hemisphere) and lambing in spring or summer.

Shetland ewes are hardy, easy lambers, good mothers and produce ample milk.