The postal system was established by the Akkadian Empire by using clay tablets in which Akkadian scripture was inscribed into the texture that listed the name and address of the person who is to receive the package along with a seal that indicated the person who was the sender. The only person who was allowed to open these letters was the person listed as the recipient, and the clay envelope ensured that would be the case since the only way to access the contents was to break the clay seal.
