Cathay Williams (1842 –1892? ) was the first and only known female Buffalo Soldier. She was born into slavery and worked for the Union army during the Civil War. She posed as a man and enlisted as Williams Cathay in the 38th infantry in 1866. She was given a medical discharge in 1868.

List under Profiles in Courage on the official US Army website GoArmy.com Cathay Williams was the first document African-American female to enlist in the U.S. Army. When Cathay Williams enlisted in the Army, women were not allowed to enlist nor serve as soldiers. So, Williams posed as a man and joined Thirty-Eighth Infantry. As a result, she became the first and the only known female Buffalo Soldier. When she enlisted as “William Cathay” a physical examination was not required. It’s unclear how she passed Army physicals and several hospitalizations in military facilities without her gender being detected. There is no record of how many women enlisted in the army during the Indian Wars. In all likelihood there were other "Cathay Williams' and like Cathay Williams they served their country.

According to a St. Louis Daily Times, January 2, 1876 interview, Private Williams described herself. In her words, "My Father a was a freeman, but my mother a slave, belonging to William Johnson, a wealthy farmer who lived at the time I was born near Independence, Jackson county, Missouri.” Private Williams stated that while she was a young girl her master and family moved to Jefferson City. Apparently, her master, William Johnson, a wealthy planter died in Jefferson City. When the war broke out and the United States soldiers came to Jefferson City they took Cathay Williams, and other “colored” folks with them to Little Rock. COL Benton of the 13th army corps was the officer that kidnapped them, according to Williams she did not want to go. The colonel wanted her to cook for the officers, but she didn’t know how to cook. She had always been a house girl.  

Private Williams stated that she learned to cook after going to Little Rock and was with the Army atThe Battle of Pea Ridge. Afterwards the command moved to various portions of Arkansas and Louisiana. She witnessed the soldiers burn lots of cotton, and was at Shreveport when the rebel gunboats were captured and burned on the Red River. The command she was with later went to New Orleans, then by way of the Gulf to Savannah Georgia, on to Macon and other places in the South. Finally she was sent to Washington City. At the time Gen. Sheridan made his raids in the Shenandoah Valley. Private Williams was cook and laundress for his staff, and was sent from Virginia to some place in Iowa and then to Jefferson Barracks, where she stayed for some time. After all that travel, according to Private Williams, “You will see by this paper that on the 15th day of November 1866 I enlisted in the United States Army at St. Louis, in the Thirty-eighth United States Infantry Company A, Capt. Charles E. Clarke commanding.” Captain Charles E. Clarke in the Civil War 6th Infantry at the Battle of Baton Rouge. The regiment wore the Zouave uniform.

According to her account, a friend and Private Williams’ cousin all joined up, and the men kept her secret. Like many women who join the military today, she stated that she wanted financial independence and a paying job. Soon after going on active duty, Williams contracted smallpox. “I got well I joined my company in New Mexico. I was as that paper says, I was never put in the guard house, no bayonet was ever put to my back. I carried my musket and did guard and other duties while in the army, but finally I got tired and wanted to get off. I played sick, complained of pains in my side, and rheumatism in my knees. The post surgeon found out I was a woman and I got my discharge,” Private Williams recounted.

After the Civil War, Congress reorganized the Army and authorized the formation of four regiments of black infantry, designated the 38th, 39th, 40th and 41st Infantry Regiments (Colored). The 38th and 41st were reorganized as the 25th Infantry Regiment, with headquarters in Jackson Barracks in New Orleans, Louisiana, in November 1869.

According to U.S. Army: On November 15, 1866, Cathay Williams enlisted in the Army using the name William Cathay. She informed her recruiting officer that she was a 22-year-old cook. He described her as 5' 9", with black eyes, black hair and black complexion. An Army surgeon examined Cathay and determined the recruit was fit for duty, thus sealing her fate in history as the first documented African-American woman to enlist in the Army even though U.S. Army regulations forbade the enlistment of women.