Rebellion Record: a Diary of American Events: Documents and Narratives, Volume 11.
Frank Moore, Ed.

[399] British possessions on the north, succeeded in combining their various and scattered tribes for a final effort against the whites, and by the opening of spring had slowly concentrated their whole force on and near the Upper Missouri, to resist the navigation of the Missouri river, prevent the passage of emigrants across the great plains, and to deliver, with their combined forces, a final battle against the United States troops under General Sully,

This Indian force was then estimated by competent authorities, and so reported by me to the War Department early in the spring, at about six thousand warriors, and this estimate was subsequently confirmed by General Sully, after his battles with them near the Little Missouri.

It was also reported at the time, and has been confirmed since by undoubted testimony, that ammunition and other necessary supplies were brought to the Indian camps during the winter by half-breeds and traders from the British settlements on the Red River of the North. It is hardly necessary for me to repeat what I have so often reported, that Indian hostilities in this department have been fomented and encouraged and the Indians supplied with the means to continue the war by the half-breeds, and other British subjects of the Selkirk settlements.

As I was satisfied that this combination of the whole of the numerous and widely-dispersed tribes of the Sioux (or Dakota) nation, who occupy the vast region north of the Platte, and the northern boundaries of Iowa, from the Rocky mountains to the vicinity of the Great Lakes, would be the final effort of the great Indian nation to continue hostilities against the whites, and as I felt sure that if once their entire force of warriors could be met and defeated this Indian war in the North-west on any considerable scale would be closed, preparations for an active campaign during the summer of 1864 were made during the close of last winter.

The plan of operations consisted in putting into the field under the command of Brigadier-General A. Sully, an active column of about two thousand five hundred men entirely cavalry, to advance against the Indians wherever they could be found and deliver battle with them, and at the same time to follow up the movement of this force with detachments of infantry large enough to establish strong posts in the Indian country.

These posts were so located as to cover the frontier of Iowa and Minnesota and the frontier settlements of Dakota territory, at a long distance; to interpose between the different tribes so as to prevent concerted action; to command the hunting grounds of the Indians so that they would be constantly under the supervision and in the power of the military forces, which by concerted action could easily and promptly march a heavy force of cavalry upon any portion of the region in which the Indians are obliged to hunt for subsistence; to command the Indian trails toward the frontier settlements, so as to detect the passage even of the smallest parties attempting to make raids upon the settlers, and to follow them up; and, so far as military necessities would allow, to protect an emigrant route from the Upper Mississippi river to the territories of Idaho and Montana. The details of this plan of operations were submitted to you and approved in February last, and immediate preparations made to carry them into execution.

General Sully collected the forces under his command from the various posts and stations in his district early in the spring, and commenced to move up the Missouri river, leaving only such detachments as were necessary to cover the frontier from small Indians raids during,his absence. He was reinforced by about one thousand five hundred mounted men from Minnesota, leaving General Sibley with about seven hundred effective men to protect the frontier settlements of Minnesota during the summer. The mouth of Burdache creek, on the Upper Missouri, was selected as the point where the Minnesota troops should join the forces of General Sully moving up the Missouri, and the junction of these forces was made on the thirtieth of June. The spring rise in the Missouri river did not come down until very late in the season, and Sully only reached the mouth of Canon Ball river, at which point he was to establish a strong post, which was to be his depot of supplies, on the seventh of July. He established Fort Rice at that point, distant from Sioux City four hundred and fifty miles, and garrisoned it with five companies of the. Thirtieth Wisconsin volunteers. The Indians, who had been concentrated on and near the Missouri river, about fifty miles above this post, had meantime crossed to the south-west side of the river and occupied a strong position in a very difficult country near the Little Missouri river, due west, and about two hundred miles from Fort Rice.

On the twenty-sixth of July, General Sully marched upon these Indians with the following forces: Eighth Minnesota volunteers (mounted) and six companies of Second Minnesota cavalry, with four light guns, under command of Colonel M. T. Thomas, Eighth Minnesota volunteers; eleven companies Sixth Iowa cavalry, three companies Seventh Iowa cavalry, two companies Dakota cavalry, four companies Brackett's battalion cavalry, one small company of scouts, and four mountain howitzers, all under command of--------, numbering in all two thousand two hundred men. A small emigrant train for Idaho, which had accompanied the Minnesota troops from that State, followed the movement of Sually's force. At the head of Heart river he corralled his trains, and leaving a sufficient guard with them, he marched rapidly to the north-west, to the point where the combined forces of the Indians were assembled. On the morning of July twenty-eighth, he came upon them — between five and six thousand warriors — strongly