In July of 1866, the United States Congress passed legislation establishing the 9th and 10th Cavalry Regiments. Both Regiments were made up entirely of Black Enlisted Soldiers and were led by white officers. The  Comanches gave the 10th Cavalry the nickname of Buffalo Soldiers because of their respect for the troops tireless pursuit and superior trail skills. The 10th Regiment adopted the name and the Buffalo became part of their coat of arms. The name later became synonymous with both regiments. The 9th and 10th Cavalry were two of the most distinguished units in Army history and were the recipients of many awards for valor and service.

The Buffalo soldiers served in New Mexico, Arizona, Texas, and throughout the western territories. They fought against Geronimo, Sitting Bull, Victorio, and Lone Wolf. The Buffalo Soldiers also explored and mapped large areas of the southwest territories. The troops protected railroad workers, strung telegraph lines, and built many of the frontier outposts. 

The Buffalo Soldiers not only had to contend with the normal rigors and hardships of frontier service, but also endured racism and hate from the very white settlers they were protecting. They were hated not only because of their skin color, but because of their Union Uniforms. (They served mostly in the Southwestern states which were still suffering the effects and resentful of having lost the Civil War.) 

Many white officers, including George Armstrong Custer refused to serve with Black soldiers. (In the case of Custer, this proved to be a blessing.)

The 9th Cavalry was initially assigned to Texas in 1867 and in 1875 were transferred to New Mexico territory. They served continuously in what is now Texas, Arizona and New Mexico until 1881 when they were transferred to Kansas and Oklahoma. The 9th was transferred to Wyoming in 1885 but were not involved in the Massacre at Wounded Knee.

The 10th Cavalry was assigned to Fort Leavenworth, Kansas in 1866.  In 1875 they were transferred to Texas and in 1885 the 10th moved to the Arizona Territories. They were transferred to the Dakota Territories in 1891.

In 1898, the 9th and 10th Cavalry fought in the Spanish-American War and took part in the charge up San Juan Hill. The 9th and 10th Cavalry were merged into the 4th Cavalry Brigade under the command of General Benjamin O. Davis Sr. in 1941.

Congressional Medal of Honor winners include: 

9th Cavalry - 1st Sergeant Moses Williams, Sergeant Thomas Boyne, Sergeant John Denny, Sergeant  George Jordan, Sergeant Henry Johnson, Sergeant Thomas Shaw, Sergeant Emanuel Stance, Sergeant Brent Woods, Corporal Clinton Greaves, Corporal William Wilson, and Private Augustus Walley.

10th Cavalry - Sergeant Major Edward Baker, Sergeant William McBryar, Private Dennis Bell, and Private Fitz Lee.