The Army Doctor was a French doctor serving in the French army, stationed in Port-Gentil, French Equatorial Africa (modern-day Gabon) during World War I. He worked at a hospital in the seaport, treating both military patients and civilian patients. His colleagues included the 2nd Army Doctor, the White Nun, and the Black Nun. It is likely that he may have also treated some of Colonel Pernod's men, many of whom had come down with tropical diseases.