Medical researcher and immunologist Carroll G. Bull was born in Jefferson County, the fourth of William Gernade and Nancy Emmaline White Bull's 11 children. Bull graduated from Harrison-Chilhowee Academy before enrolling at Carson-Newman College in 1901. He graduated from Peabody College in Nashville in 1907, with a Bachelor of Science degree. In 1910 Bull completed his medical degree at Lincoln Memorial University.
Bull served as Professor of Pathology and Bacteriology at LMU from 1910 to 1912. In 1913 he became Assistant in Pathology at New York's Rockefeller Institute for Medical Research. Four years later he identified the gas gangrene toxin and antitoxin, becoming the first American to discover an antitoxin of any kind.
The gas gangrene infection posed an immense problem for doctors treating the wounded in World War I and claimed many lives and limbs. In November 1917 Bull accepted a major's commission in the United States Army Medical Corps, where he promoted the production and use of his antitoxin on battlefields and in hospitals. France honored him for his efforts with its Silver Medaille de Reconnaissance Francaise.
Earlier in 1917 Bull received an appointment as Associate Professor of Immunology at Johns Hopkins School of Hygiene and Public Health in Baltimore, where he helped establish the Immunology department. Bull made outstanding contributions to medicine through his work on diphtheria, malaria, pneumonia, and the agglutination of bacteria. His work helped establish the basis for current immunological theory. In 1922 Bull was promoted to Professor of Immunology. He died on May 31, 1931.