Native Americans have made up an integral part of American military conflicts since the Colonial period. Colonists recruited Indian allies during conflicts such as the Pequot War, the French and Indian Wars, the Revolutionary War, as well as in War of 1812. Native Americans also fought on both sides during the American Civil War, as well as military missions abroad including the most notable, the Codetalkers who served in World War II. The Scouts were active in the American West in the late 19th and early 20th centuries. Including those who accompanied General John J. Pershing in 1916 on his expedition to Mexico in pursuit of Pancho Villa. Indian Scouts were officially deactivated in 1947 when their last member retired from the Army at Fort Huachuca, Arizona. For many Indians it was an important form of interaction with European-American culture and their first major encounter with the Whites' way of thinking and doing things.

Recruitment of Indian scouts was first authorized on July 28, 1866 by an act of Congress.

"The President is authorized to enlist and employ in the Territories and Indian country a force of Indians not to exceed one thousand to act as scouts, who shall receive the pay and allowances of cavalry soldiers, and be discharged whenever the necessity for further employment is abated, at the discretion of the department commander."

There were different types of scouts, some enlisted as Indian Scouts for brief terms and there were others who were hired as scouts by the U.S. Army. Some individual may have served at different times as a hired scout and an enlisted scout. Prior to the act in 1866 these scouts were considered employees rather than soldiers. Enlistment records and muster rolls, from 1866 to 1912 were in many instances filed by state, some records were broken down by company or military post providing information such as when, where, and by whom the scout was enlisted; period of enlistment; place of birth; age at time of enlistment; physical description; and possibly additional remarks such as discharge information, including date and place of discharge, rank at the time, and if the scout died in service. Indian scouts who were officially enlisted in the army after 1866 were issued old pattern uniforms from surplus stock legally exempt from sale. Their uniforms were worn with less regulation, sometimes mixed with their native dress. In 1870, Captain Bourke of the 3rd Cavalry described Apache scouts in Arizona as "almost naked, their only clothing being a muslin loin-cloth, a pair of point toed moccasins and a hat of hawk feather". In 1876 a description of Crow Scouts reads that they wore, "an old black army hat with top cut out and sides bound round with feathers, fur and scarlet cloth". With the availability of army clothing some Native scouts took advantage of the availability of the clothing. In 1902 when new regulations were introduced in March the U.S. Scouts received a new more regulated uniform.

In the Indian wars following the U.S. Civil War, the Indian Scouts were a fast-moving, aggressive, and knowledgeable asset to the U.S. Army. They often proved to be immune to army notions of discipline and demeanor, but they proved expert in traversing the vast distances of the American West and providing intelligence—and often a shock force—to the soldiers who sought hostile Indians.^{[citation needed]} Pawnee Scout leader Luther H. North commented, "Neither the Wild Tribes, nor the Government Indian Scouts ever adopted any of the White soldier's tactics. They thought their own much better." Another chief of scouts, Stanton G. Fisher, emphasized the importance of Indian Scouts by saying of the soldiers, "Uncle Sam's boys are too slow for this business."

In 1892 1st Lieutenant Hugh L. Scott organized Troop L of the 7th Cavalry Regiment at Fort Sill, Oklahoma. All of its enlisted men in Troop L were Indian Scouts. The troop served until 1897 when the enlistments of the Scouts expired and it was disbanded. Scott would rise to the rank of major general and served as Chief of Staff of the United States Army from 1914 to 1917.

The last detachment of Indian Scouts served at Fort Huachuca, Arizona in 1942.

During the Indian wars, scouts were able to detect horse tracks where other soldiers could only detect hard ground. From these tracks, scouts could estimate the number of horses in a group. From the moisture content of horse dung, scouts could estimate the age of the trail. Scouts were also able to discern whether females rode with a group based on the position of a horse's urine within its tracks - women sometimes/often rode mares while men rode stallions.