B.J. Palmer, the developer of chiropractic was instrumental in getting chiropractic recognized as a licensed profession. Although many chiropractors were jailed for "practicing medicine without a license". Bj did much to increase the acceptance of chiropractic and fought for chiropractors to be recognized not as a form of medical practice but a separate and distinct entity.
Chiropractic and its leaders have changed and evolved through the years but the principles of this distinct healing method are still the same as they were over 100 years ago. Essentially the body is a self-healing organism. The nervous system controls and coordinates every organ and tissue of the body. The relationship between the spine and the nervous system is a predictor of state of health. Find the interference (subluxation) correct it and the body will always move back toward health.