The Black Nun was a member of a religious order worked in the hospital in Port-Gentil, French Equatorial Africa (modern-day Gabon) during World War I. She tended to the medical and spiritual needs of the patients and visitors. Her colleagues included the White Nun, and the Army Doctor and 2nd Army Doctor. Given that she worked with patients in the hospital, it is likely that she had some basic education in nursing, as well as her role as a member of a Catholic order of nuns.