We come now to the Sioux outbreak of 1890, but before going into the history of this short but costly war it is appropriate to state briefly the causes of the outbreak. In the documentary appendix to this chapter these causes are fully set forth by competent authorities—civilian, military, missionary, and Indian. They may be summarized as (1) unrest of the conservative element under the decay of the old life, (2) repeated neglect of promises made by the government, and (3) hunger. The Sioux are the largest and strongest tribe within the United States. In spite of wars, removals, and diminished food supply since the advent of the white man, they still number nearly 26,000. In addition to these there are about 600 more residing in Canada. They formerly held the headwaters of the Mississippi, extending eastward almost to Lake Superior, but were driven into the prairie about two centuries ago by their enemies, the Ojibwa, after the latter had obtained firearms from the French. On coming out on the buffalo plains they became possessed of the horse, by means of which reinforcement to their own overpowering numbers the Sioux were soon enabled to assume the offensive, and in a short time had made themselves the undisputed masters of an immense territory extending, in a general way, from Minnesota to the Rocky mountains and from the Yellowstone to the Platte. A few small tribes were able to maintain their position within these limits, but only by keeping close to their strongly built permanent villages on the Missouri. Millions of buffalo to furnish unlimited food supply, thousands of horses, and hundreds of miles of free range made the Sioux, up to the year 1868, the richest and most prosperous, the proudest, and withal, perhaps, the wildest of all the tribes of the plains. In that year, in pursuance of a policy inaugurated for bringing all the plains tribes under the direct control of the government, a treaty was negotiated with the Sioux living west of the Missouri by which they renounced their claims to a great part of their territory and had “set apart for their absolute and undisturbed use and occupation”—so the treaty states—a reservation which embraced all of the present state of South Dakota west of Missouri river. At the same time agents were appointed and agencies established for them; annuities and rations, cows, physicians, farmers, teachers, and other good things were promised them, and they agreed to allow railroad routes to be surveyed and built and military posts to be established in their territory and neighborhood. At one stroke they were reduced from a free nation to dependent wards of the government. It was stipulated also that they should be allowed to hunt within their old range, outside the limits of the reservation, so long as the buffalo abounded—a proviso which, to the Indians, must have meant forever.