Original
The earliest reported mention of Celiac Disease comes from a Greek physician, Aretaeus of Cappadocia in the first century AD (ref. Dr. Stephano Guandalini, M.D.)
19th century's Dr. Mathew Baillie published his observations of chronic diarrheal disorders in adults who seemed to feel better living almost entirely on rice.
The most recent "discovery" comes from an English doctor, Samuel Gee in 1888.
Around 1920-1940, babies were being brought to hospitals and dying from diarrhea and malnutrition. They discovered that a diet solely comprised of bananas helped them recover.