Cheyenne Expedition of 1857.—In the spring of 1857 the Cheyennes became somewhat troublesome on the western frontier, On May 18 Col. F. V. Sumner despatched Maj. Sedgwick with four companies of cavalry up the Arkansas river, and two days later left Fort Leavenworth with a force of cavalry and infantry, intending to meet Sedgwick on the south fork of the Platte on July 4. The union was effected, and after leaving two companies of dragoons at Fort Laramie for Gen. Harney's Utah expedition, Sumner moved over to the Solomon river. On July 29, while passing down the Solomon in pursuit of the Indians, he came upon some 300 Cheyennes drawn up in battle array. Sumner charged and put the Indians to flight, killing 9 and wounding a large number, with a loss of 2 killed and 9 wounded. On the 31st he reached the Indian village, which he found deserted, with 171 lodges still standing and nearly as many more taken down ready for removal. Everything indicated a precipitate flight, and after destroying the village, Sumner continued the pursuit to within 40 miles of the Arkansas river.

While encamped near old Fort Atkinson, on Aug. 11, he received information that the Cheyennes refused to come to Dent's fort, where the agent was waiting to distribute their annual presents, and that they had notified the agent that he would not be permitted to take the goods out of the country. Sumner wrote to the adjutant-general of the United States army, imparting this information, and adding: "I have therefore decided to proceed at once to Bent's fort with the elite of my cavalry, in the hope that I may find the Cheyennes collected in that vicinity, and, by further blow, force them to sue for peace; at all events this movement will secure the agent and the public property."

Before reaching Bent's fort, Sumner received an order to break up the expedition and send four companies of cavalry to join Gen. Harney's expedition. The latter part of the order was subsequently countermanded, and on Sept. 16 the expedition reached Fort Leavenworth, having traveled over 1,800 miles.