The first examples of the protection of personal data can be found early on in world history:
Hippocratic oath
The
Hippocratic oath was introduced in 400 BC: Doctors pledge to keep their patients' secrets confidential. The forerunner of medical confidentiality.
Confessional secrecy
In 1215 AD, the heads of the Catholic Church incorporated the secrecy of confession into canon law. Clergymen are thus obliged to maintain secrecy about what is confided to them in confession.
Secrecy of correspondence
In the 18th century, the
secrecy of correspondence was enshrined in law in some countries. In France, a decree issued by Louis XV even made breaking open letters and parcels punishable by death.