The origins of hypnosis extend back to the ancient temples of Aesculapius, the Greek god of medicine, where advice and reassurance uttered by priests to sleeping patients was interpreted by the patients as the gods speaking to them in their dreams.Interest in hypnosis was revived in France in the late 1880s by Jean Martin Charcot, a neurologist, who thought that hypnosis and hysteria both reflected a disorder of the central nervous system. In opposition to Charcot's neurological theories, A.A. Liebeault and Hippolyte Bernheim, two other French physicians, emphasized the role of suggestibility in producing hypnotic effects. Pierre Janet and Sigmund Freud also studied with Charcot, and Freud began to develop his psycho-social theories of mental illness after observing the suggestibility of hysterical patients when they were hypnotized.

William James and other early psychologists became interested in hypnosis because it seemed to involve changes in conscious awareness. The first systematic experimental work on hypnosis was reported by P.C. Young, in a doctoral dissertation completed at Harvard in 1923, and by Clark Hull in an extensive series of experiments initiated at the University of Wisconsin in the 1920s and continued at Yale into the 1930s. Also at Wisconsin during Hull's time was Milton Erickson, a physician whose provocative clinical and experimental studies stimulated interest in hypnosis among psychotherapists (Hull knew Erickson at Wisconsin, but the immediate source of Hull's interest in hypnosis was Joseph Jastrow, a prominent psychologist, who was Hull's mentor). After World War II, interest in hypnosis rose rapidly. Ernest Hilgard, together with Josephine Hilgard and Andre Weitzenhoffer, founded a laboratory for hypnosis research at Stanford University. Hilgard's status as one of the world's most distinguished psychologists helped establish hypnosis as a legitimate subject of scientific inquiry. Also important in this revival were Martin Orne, Theodore X. Barber, Theodore Sarbin, and Erika Fromm.