The history of the mails also allows for interesting glimpses into the evolution of social and political institutions. In ancient times letters were exchanged for the purposes of official business, providing rulers and nobles with intelligence about goings-on in the outer reaches of their empires, or with progress reports on military campaigns. Only merchants were permitted to carry on private business correspondence. With the increasing importance of the postal communication networks for the administering of vast territories, scribes became a semi-privileged class. Literacy became a ticket to success, stature, and, to a certain extent, power. A similar development occurred during the Middle Ages, as the Catholic Church gained political power. Since letters were exchanged for church business only, monks and church dignitaries became a literate class and a bureaucracy unto themselves.
The first glimmers of democratization of the mails can be traced to the rise of the medieval universities, which set up independent courier systems for their students. The mail carriers often took private letters along if the destinations fit into their routes. The rise of the merchant classes created city states, mercantilism, and the need for increased diplomatic communications. By the early Renaissance, private postal organizations, notably at Thurn and Taxis, were already extending their relay networks all over Europe. Having secured charters and guarantees of safe conduct from the rulers of many countries, they carried private as well as official mail.
As the postal business became profitable (Thurn and Taxis built the first financial empire without extensive property holdings—the predecessor to multi-national corporations), governments forcibly bought out the private mail services and used the tariffs as taxes to support armies and wars for territorial gain. By the middle of the 19th century postal systems in
countries had reverted to state ownership. This development proved to be a mixed blessing. While states fixed rates which virtually everyone could afford (in the U.S. Letters were delivered free within cities from 1873 on, free rural delivery was established in 1896), they also asserted state control and authority, facilitating a return to the ancient practice of governmental snooping and censorship.