WHERE DID THE PLAINS INDIANS GET THEIR HORSES

LTHOUGH horses were unknown to the Indians of North America A before the advent of the Spaniards, many of the tribes living in the great plains area were already in possession of these animals before the first explorers and traders reached them. This rapid diffusion of the horse well in advance of the on-coming white men proved an important factor in the subsequent history of the West and has caused a great deal of speculation concerning the details of such spread. Because of the supposedly favorable environment for horses throughout most of the area west of the Mississippi, there has been little question that the natural increase of a comparatively small starting herd could have furnished an ample supply for the whole area in the course of a century or two, much as the herd of twelve in South America spread over the pampas there in a much shorter time. The chief difficulty has been to determine the place of origin of the original stock, and with it the date of starting. Once this had been determined, it would be easier to trace the resulting lines of distribution and to approximate the rate of spread. Possibly the most detailed work on this topic has been done by Clark Wissler, who has written on the influence of the horse on the culture of the Plains Indian. He indicates that animals lost or abandoned by the DeSoto and Coronado expeditions in the period 1540-1542 probably furnished the parent stock. With such an early introduction, horses could have reached the limits of their natural range by 1600. He says ". . . for all we know, the Crow and Blackfoot, for instance, may have had horses for 150 years before their first mention in 1742 and 17.51."' While few writers agree that the horses could have reached their northern limits so soon, many favor this theory that the strays from either or both of the expeditions multiplied rapidly on the plains and were adopted by the Indians before their next contacts with the whites. Since this theory was so commonly accepted, it seemed that a careful search of source material should disclose a few items bearing on the subject which would, even though indirectly, substantiate such an explanation. The search for such items surprised me greatly. The evidence and deductions all indicated that the theory was highly improbable. The following argument is offered in support of this statement. How many horses must have been lost or abandoned a t one spot in