Cathay Williams (1844-1893) was born in Independence, Missouri. Her mother was a slave and her father was free. She worked as a house slave on the Johnson plantation on the outskirts of Jefferson City, Missouri.

In 1861, Union forces occupied Jefferson City during the early stages of the Civil War. Like other captured slaves, she was designated as contraband and served as an Army cook and washerwoman. In this role, she accompanied the infantry all over the country. Williams served under the service of General Philip Sheridan and witnessed the Red River Campaign and the Battle of Pea Ridge.

She enlisted voluntarily when she was 17 in 1866. Because of the prohibition against women serving in the military, she enlisted as a man, under the name of "William Cathay". Williams was assigned to the 38th U.S. Infantry Regiment for three years.

Due to health issues, a surgeon finally discovered she was a woman and informed the post commander. She was honorably discharged by her commanding officer, Captain Charles E. Clarke, on October 14, 1868. She then signed up with an emerging all-black regiment that would eventually become part of the legendary Buffalo Soldiers.

Following her discharge, Williams worked as a cook and seamstress. She had a troubled marriage and had her husband arrested after he stole her money and a team of horses. It was during this time that her story first became public. A reporter from St. Louis heard rumors of a female African-American who had served in the army and came to interview her. Her life and military service narrative was published in the St. Louis Daily Times on January 2, 1876.

Suffering from neuralgia and diabetes, she was denied a military pension in 1893. The exact date of her death is unknown, but it is believed she died shortly after she was denied.