A detachment of Maj. Stephen H. Long’s Yellowstone exploring expedition, under command of Capt. Wyley Martin, spent the winter of 1818–19 on Cow Island, which now belongs to Atchison county, and established a post known as Cantonment Martin. This was the first United States military post established above Ft. Osage, and west of Missouri Territory. During that winter Captain Martin’s men killed between 2,000 and 3,000 deer, besides great numbers of bears, turkeys and other game. The troops that established this frontier post were a part of the First Rifle regiment, the “crack” organization of the United States army at that time. In July, 1819, Major Long arrived at Cow Island. His steamboats were the first to ascend the Missouri river above Ft. Osage. The next day Colonel Chambers and a detachment of infantry arrived. Thomas Say and his party of naturalists, under command of Major Biddle, at about the same time crossed Atchison county en route from the Kansa Indian village where Manhattan now stands, and joined Major Long’s party at Cow Island. Messrs. Say and Jessup, naturalists of the expedition, were taken very ill and had to remain at the island for some time. Col. Henry Atkinson, the founder of Ft. Atkinson, and commander of the western department for more than twenty years, arrived at Cow Island shortly after Major Long. Maj. John O’Fallon was sutler of the post and Indian agent for the upper Missouri. On July 4, 1819, the Nation’s birthday was celebrated on Cow Island. The flags were raised at full mast, guns were fired, and they had “pig with divers tarts to grace the table.” On August 24 an important council with the Kansa Indians was held on the island. An account of this council will be found in the chapter on Indian history in this volume. One of the captains who was stationed on Cow Island—Bennett Riley— afterwards became a distinguished man in the history of this country. He was the man for whom Ft. Riley was named. He served with gallantry in the Indian country, the Northwest and Florida. In the Florida war he was promoted to colonel. In the war with Mexico he became a major-general, and was subsequently military governor of California. Col. John O’Fallon entered the army from Kentucky and fought in the Battle of Tippecanoe under Harrison, where he was severely wounded and carried the scar to his grave. He had a brilliant military record, and afterwards became one of the wealthiest and most public-spirited citizens of St. Louis. Major Willoughby Morgan assumed command of the Cow Island post April 13, 1819. He was also a distinguished officer. When Cantonment Martin was abandoned in September, 1819, it required a month to transport the troops from there to Council Bluffs on the steamboats.