List of Famous people named Theobald

Prof Theobald Smith FRS(For) HFRSE was a pioneering epidemiologist, bacteriologist, pathologist and professor. He is widely considered to be America's first internationally significant medical research scientist. His work included the study of Texas cattle fever and the epidemiology of cattle infected by ticks transmitting protozoa. He also discovered a species of Salmonella, named for his chief Daniel E. Salmon, and studied anaphylaxis, then referred to as Theobald Smith phenomenon. Smith taught at Columbian University and established the school's department of bacteriology, the first at a medical school in the United States. He also worked at Harvard University and the Rockefeller Institute.

Saint Theobald of Marly was a French abbot and saint. He was born at the castle of Marly, Montmorency, and was trained as a knight. He served as a knight at the court of Philip Augustus, though he later entered the Cistercian monastery of Vaux-de-Cernay in 1220. He was elected prior in 1230 and ninth abbot in 1235. He was held in high esteem by Saint Louis.

Theobald le Vieux of Blois, also called Theobald the Elder (890-917) was a Count of Chartres in medieval France.

Théobald Dillon was count of Dillon and an Irish-born general in the French army. He was the grandson of Arthur Dillon, the nephew of the bishop Arthur Richard Dillon and the cousin of general Arthur Dillon.