history
The first evidence of spotted horses on the Columbia Plateau can be found in the journals of the Lewis and Clark Expedition of February 15, 1806.
[Lewis] Saturday, February 15, 1806; The horse is predominantly withheld from the nations that inhabit the great prairies of Columbia, stretching from the 40th to the 50th parallel north and the landing line between the Rocky Mountains and several mountains that run along the Columbia River to the Make Great Falls from longitude 116-121. This vast area, which is basically unforested, is inhabited by the following natives: Sosone or Snake Indians, Chopunnish, Sokulks, Cutssahnims, Chymnapums, E [c] helutes, Eneshuh and Chilluckkittequaws. All of them enjoyed the benefit of the meek, noble, and precious animal, the horse, and all of them but the last three had immensely large herds. Their horses appear to be of excellent breed, lofty, elegantly formed, active and enduring animals; In short, many of them look like the fine English coarsers (thoroughbreds) and cut a fine figure in every country. Some of these horses are pided (variegated, spotted) with large white, irregularly spaced spots mixed with black, brown, bay or some other dark color. Most of them, however, are monochrome with a star, snip and white feet, or in other words, similar to our best thoroughbred horses in Virginia. They are also similar to them in speed, shape and color. The natives keep them in great numbers on the prairies and the grass that grows there is their only livelihood and their owners don't bother to stockpiling them for the winter, but with little work they stay with the dry grass of the prairie during the Winter fat. (Lewis and Clark Journals - RG Thwaites 1904)